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Fu R, Qu Y, Xue M, Liu X, Chen S, Zhao Y, Chen R, Li B, Weng H, Liu Q, Dai Q, Chen J. Manipulating hyperbolic transient plasmons in a layered semiconductor. Nat Commun 2024; 15:709. [PMID: 38267417 PMCID: PMC10808201 DOI: 10.1038/s41467-024-44971-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Accepted: 01/10/2024] [Indexed: 01/26/2024] Open
Abstract
Anisotropic materials with oppositely signed dielectric tensors support hyperbolic polaritons, displaying enhanced electromagnetic localization and directional energy flow. However, the most reported hyperbolic phonon polaritons are difficult to apply for active electro-optical modulations and optoelectronic devices. Here, we report a dynamic topological plasmonic dispersion transition in black phosphorus via photo-induced carrier injection, i.e., transforming the iso-frequency contour from a pristine ellipsoid to a non-equilibrium hyperboloid. Our work also demonstrates the peculiar transient plasmonic properties of the studied layered semiconductor, such as the ultrafast transition, low propagation losses, efficient optical emission from the black phosphorus's edges, and the characterization of different transient plasmon modes. Our results may be relevant for the development of future optoelectronic applications.
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Affiliation(s)
- Rao Fu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences & School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Yusong Qu
- CAS Key Laboratory of Nanophotonic Materials and Devices, National Center for Nanoscience and Technology & School of Nanoscience and Engineering, University of Chinese Academy of Sciences, Beijing, 100190, China
| | | | - Xinghui Liu
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi, 030006, China
| | - Shengyao Chen
- MOE Key Laboratory of Weak-Light Nonlinear Photonics, TEDA Institute of Applied Physics, School of Physics, Nankai University, Tianjin, 300457, China
| | - Yongqian Zhao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences & School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, 325001, China
| | - Runkun Chen
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, 350002, China
| | - Boxuan Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences & School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Hongming Weng
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences & School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| | - Qian Liu
- CAS Key Laboratory of Nanophotonic Materials and Devices, National Center for Nanoscience and Technology & School of Nanoscience and Engineering, University of Chinese Academy of Sciences, Beijing, 100190, China.
- MOE Key Laboratory of Weak-Light Nonlinear Photonics, TEDA Institute of Applied Physics, School of Physics, Nankai University, Tianjin, 300457, China.
| | - Qing Dai
- CAS Key Laboratory of Nanophotonic Materials and Devices, National Center for Nanoscience and Technology & School of Nanoscience and Engineering, University of Chinese Academy of Sciences, Beijing, 100190, China.
| | - Jianing Chen
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences & School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China.
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China.
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Chen M, de Oliveira TVAG, Ilyakov I, Nörenberg T, Kuschewski F, Deinert JC, Awari N, Ponomaryov A, Kuntzsch M, Kehr SC, Eng LM, Gensch M, Kovalev S. Terahertz-slicing - an all-optical synchronization for 4 th generation light sources. Opt Express 2022; 30:26955-26966. [PMID: 36236877 DOI: 10.1364/oe.454908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 06/01/2022] [Indexed: 06/16/2023]
Abstract
A conceptually new approach to synchronizing accelerator-based light sources and external laser systems is presented. The concept is based on utilizing a sufficiently intense accelerator-based single-cycle terahertz pulse to slice a thereby intrinsically synchronized femtosecond-level part of a longer picosecond laser pulse in an electro-optic crystal. A precise synchronization of the order of 10 fs is demonstrated, allowing for real-time lock-in amplifier signal demodulation. We demonstrate successful operation of the concept with three benchmark experiments using a 4th generation accelerator-based terahertz light source, i.e. (i) far-field terahertz time-domain spectroscopy, (ii) terahertz high harmonic generation spectroscopy, and (iii) terahertz scattering-type scanning near-field optical microscopy.
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3
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Sternbach AJ, Ruta FL, Shi Y, Slusar T, Schalch J, Duan G, McLeod AS, Zhang X, Liu M, Millis AJ, Kim HT, Chen LQ, Averitt RD, Basov DN. Nanotextured Dynamics of a Light-Induced Phase Transition in VO 2. Nano Lett 2021; 21:9052-9060. [PMID: 34724612 DOI: 10.1021/acs.nanolett.1c02638] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We investigate transient nanotextured heterogeneity in vanadium dioxide (VO2) thin films during a light-induced insulator-to-metal transition (IMT). Time-resolved scanning near-field optical microscopy (Tr-SNOM) is used to study VO2 across a wide parameter space of infrared frequencies, picosecond time scales, and elevated steady-state temperatures with nanoscale spatial resolution. Room temperature, steady-state, phonon enhanced nano-optical contrast reveals preexisting "hidden" disorder. The observed contrast is associated with inequivalent twin domain structures. Upon thermal or optical initiation of the IMT, coexisting metallic and insulating regions are observed. Correlations between the transient and steady-state nano-optical textures reveal that heterogeneous nucleation is partially anchored to twin domain interfaces and grain boundaries. Ultrafast nanoscopic dynamics enable quantification of the growth rate and bound the nucleation rate. Finally, we deterministically anchor photoinduced nucleation to predefined nanoscopic regions by locally enhancing the electric field of pump radiation using nanoantennas and monitor the on-demand emergent metallicity in space and time.
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Affiliation(s)
- Aaron J Sternbach
- Department of Physics, Columbia University, New York, New York 10027, United States
| | - Francesco L Ruta
- Department of Physics, Columbia University, New York, New York 10027, United States
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, United States
| | - Yin Shi
- Department of Materials Science and Engineering, The Pennsylvania State University, State College, Pennsylvania 16801,United States
| | - Tetiana Slusar
- Electronics and Telecommunications Research Institute, Daejeon 34129, Republic of Korea
| | - Jacob Schalch
- Department of Physics, University of California San Diego, San Diego, California 92093, United States
| | - Guangwu Duan
- Department of Physics, Boston University, Boston, Massachusetts 02215, United States
| | - Alexander S McLeod
- Department of Physics, Columbia University, New York, New York 10027, United States
| | - Xin Zhang
- Department of Physics, Boston University, Boston, Massachusetts 02215, United States
| | - Mengkun Liu
- Department of Physics, Stony Brook University, Stony Brook, New York 11790, United States
| | - Andrew J Millis
- Department of Physics, Columbia University, New York, New York 10027, United States
| | - Hyun-Tak Kim
- Electronics and Telecommunications Research Institute, Daejeon 34129, Republic of Korea
| | - Long-Qing Chen
- Department of Materials Science and Engineering, The Pennsylvania State University, State College, Pennsylvania 16801,United States
| | - Richard D Averitt
- Department of Physics, University of California San Diego, San Diego, California 92093, United States
| | - D N Basov
- Department of Physics, Columbia University, New York, New York 10027, United States
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4
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Barnett J, Wehmeier L, Heßler A, Lewin M, Pries J, Wuttig M, Klopf JM, Kehr SC, Eng LM, Taubner T. Far-Infrared Near-Field Optical Imaging and Kelvin Probe Force Microscopy of Laser-Crystallized and -Amorphized Phase Change Material Ge 3Sb 2Te 6. Nano Lett 2021; 21:9012-9020. [PMID: 34665620 DOI: 10.1021/acs.nanolett.1c02353] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Chalcogenide phase change materials reversibly switch between non-volatile states with vastly different optical properties, enabling novel active nanophotonic devices. However, a fundamental understanding of their laser-switching behavior is lacking and the resulting local optical properties are unclear at the nanoscale. Here, we combine infrared scattering-type scanning near-field optical microscopy (SNOM) and Kelvin probe force microscopy (KPFM) to investigate four states of laser-switched Ge3Sb2Te6 (as-deposited amorphous, crystallized, reamorphized, and recrystallized) with nanometer lateral resolution. We find SNOM to be especially sensitive to differences between crystalline and amorphous states, while KPFM has higher sensitivity to changes introduced by melt-quenching. Using illumination from a free-electron laser, we use the higher sensitivity to free charge carriers of far-infrared (THz) SNOM compared to mid-infrared SNOM and find evidence that the local conductivity of crystalline states depends on the switching process. This insight into the local switching of optical properties is essential for developing active nanophotonic devices.
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Affiliation(s)
- Julian Barnett
- I. Institute of Physics (IA), RWTH Aachen, 52074 Aachen, Germany
| | - Lukas Wehmeier
- Institute of Applied Physics, Technische Universität Dresden, 01062 Dresden, Germany
- ct.qmat, Dresden-Würzburg Cluster of Excellence-EXC 2147, Technische Universität Dresden, 01062 Dresden, Germany
| | - Andreas Heßler
- I. Institute of Physics (IA), RWTH Aachen, 52074 Aachen, Germany
| | - Martin Lewin
- I. Institute of Physics (IA), RWTH Aachen, 52074 Aachen, Germany
| | - Julian Pries
- I. Institute of Physics (IA), RWTH Aachen, 52074 Aachen, Germany
| | - Matthias Wuttig
- I. Institute of Physics (IA), RWTH Aachen, 52074 Aachen, Germany
| | - J Michael Klopf
- Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - Susanne C Kehr
- Institute of Applied Physics, Technische Universität Dresden, 01062 Dresden, Germany
| | - Lukas M Eng
- Institute of Applied Physics, Technische Universität Dresden, 01062 Dresden, Germany
- ct.qmat, Dresden-Würzburg Cluster of Excellence-EXC 2147, Technische Universität Dresden, 01062 Dresden, Germany
| | - Thomas Taubner
- I. Institute of Physics (IA), RWTH Aachen, 52074 Aachen, Germany
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5
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Yao Z, Chen X, Wehmeier L, Xu S, Shao Y, Zeng Z, Liu F, Mcleod AS, Gilbert Corder SN, Tsuneto M, Shi W, Wang Z, Zheng W, Bechtel HA, Carr GL, Martin MC, Zettl A, Basov DN, Chen X, Eng LM, Kehr SC, Liu M. Probing subwavelength in-plane anisotropy with antenna-assisted infrared nano-spectroscopy. Nat Commun 2021; 12:2649. [PMID: 33976184 PMCID: PMC8113487 DOI: 10.1038/s41467-021-22844-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 03/29/2021] [Indexed: 02/03/2023] Open
Abstract
Infrared nano-spectroscopy based on scattering-type scanning near-field optical microscopy (s-SNOM) is commonly employed to probe the vibrational fingerprints of materials at the nanometer length scale. However, due to the elongated and axisymmetric tip shank, s-SNOM is less sensitive to the in-plane sample anisotropy in general. In this article, we report an easy-to-implement method to probe the in-plane dielectric responses of materials with the assistance of a metallic disk micro-antenna. As a proof-of-concept demonstration, we investigate here the in-plane phonon responses of two prototypical samples, i.e. in (100) sapphire and x-cut lithium niobate (LiNbO3). In particular, the sapphire in-plane vibrations between 350 cm-1 to 800 cm-1 that correspond to LO phonon modes along the crystal b- and c-axis are determined with a spatial resolution of < λ/10, without needing any fitting parameters. In LiNbO3, we identify the in-plane orientation of its optical axis via the phonon modes, demonstrating that our method can be applied without prior knowledge of the crystal orientation. Our method can be elegantly adapted to retrieve the in-plane anisotropic response of a broad range of materials, i.e. subwavelength microcrystals, van-der-Waals materials, or topological insulators.
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Affiliation(s)
- Ziheng Yao
- grid.36425.360000 0001 2216 9681Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY USA ,grid.184769.50000 0001 2231 4551Advanced Light Source Division, Lawrence Berkeley National Laboratory, Berkeley, CA USA
| | - Xinzhong Chen
- grid.36425.360000 0001 2216 9681Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY USA
| | - Lukas Wehmeier
- grid.4488.00000 0001 2111 7257Institute of Applied Physics, Technische Universität Dresden, Dresden, Germany ,grid.4488.00000 0001 2111 7257ct.qmat, Dresden-Würzburg Cluster of Excellence-EXC 2147, Technische Universität Dresden, Dresden, Germany
| | - Suheng Xu
- grid.36425.360000 0001 2216 9681Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY USA ,grid.21729.3f0000000419368729Department of Physics, Columbia University, New York, NY USA
| | - Yinming Shao
- grid.21729.3f0000000419368729Department of Physics, Columbia University, New York, NY USA
| | - Zimeng Zeng
- grid.12527.330000 0001 0662 3178State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing, China
| | - Fanwei Liu
- grid.12527.330000 0001 0662 3178State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing, China
| | - Alexander S. Mcleod
- grid.21729.3f0000000419368729Department of Physics, Columbia University, New York, NY USA
| | - Stephanie N. Gilbert Corder
- grid.184769.50000 0001 2231 4551Advanced Light Source Division, Lawrence Berkeley National Laboratory, Berkeley, CA USA
| | - Makoto Tsuneto
- grid.36425.360000 0001 2216 9681Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY USA
| | - Wu Shi
- grid.184769.50000 0001 2231 4551Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA USA ,grid.47840.3f0000 0001 2181 7878Department of Physics, University of California, Berkeley, CA USA ,grid.8547.e0000 0001 0125 2443Institute of Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai, China
| | - Zihang Wang
- grid.47840.3f0000 0001 2181 7878Department of Physics, University of California, Berkeley, CA USA
| | - Wenjun Zheng
- grid.36425.360000 0001 2216 9681Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY USA
| | - Hans A. Bechtel
- grid.184769.50000 0001 2231 4551Advanced Light Source Division, Lawrence Berkeley National Laboratory, Berkeley, CA USA
| | - G. L. Carr
- grid.202665.50000 0001 2188 4229National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY USA
| | - Michael C. Martin
- grid.184769.50000 0001 2231 4551Advanced Light Source Division, Lawrence Berkeley National Laboratory, Berkeley, CA USA
| | - Alex Zettl
- grid.184769.50000 0001 2231 4551Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA USA ,grid.47840.3f0000 0001 2181 7878Department of Physics, University of California, Berkeley, CA USA
| | - D. N. Basov
- grid.21729.3f0000000419368729Department of Physics, Columbia University, New York, NY USA
| | - Xi Chen
- grid.12527.330000 0001 0662 3178State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing, China
| | - Lukas M. Eng
- grid.4488.00000 0001 2111 7257Institute of Applied Physics, Technische Universität Dresden, Dresden, Germany ,grid.4488.00000 0001 2111 7257ct.qmat, Dresden-Würzburg Cluster of Excellence-EXC 2147, Technische Universität Dresden, Dresden, Germany
| | - Susanne C. Kehr
- grid.4488.00000 0001 2111 7257Institute of Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Mengkun Liu
- grid.36425.360000 0001 2216 9681Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY USA ,grid.202665.50000 0001 2188 4229National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY USA
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Virmani D, Bylinkin A, Dolado I, Janzen E, Edgar JH, Hillenbrand R. Amplitude- and Phase-Resolved Infrared Nanoimaging and Nanospectroscopy of Polaritons in a Liquid Environment. Nano Lett 2021; 21:1360-1367. [PMID: 33511844 DOI: 10.1021/acs.nanolett.0c04108] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Polaritons allow for strong light-matter coupling and for highly sensitive analysis of (bio)chemical substances and processes. Nanoimaging of the polaritons' evanescent fields is critically important for experimental mode identification and field confinement studies. Here we describe two setups for polariton nanoimaging and spectroscopy in liquid. We first demonstrate the mapping of localized plasmon polaritons in metal antennas with a transflection infrared scattering-type scanning near-field optical microscope (s-SNOM), where the tip acts as a near-field scattering probe. We then demonstrate a total internal reflection (TIR)-based setup, where the tip is both launching and probing ultraconfined polaritons in van der Waals materials (here phonon polaritons in hexagonal boron nitride flakes), laying the foundation for s-SNOM-based polariton interferometry in liquid. Our results promise manifold applications, for example, in situ studies of strong coupling between polaritons and molecular vibrations or chemical reactions at the bare or functionalized surfaces of polaritonic materials.
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Affiliation(s)
- Divya Virmani
- CIC nanoGUNE BRTA, Tolosa Hiribidea 76, 20018 Donostia-San Sebastián, Spain
| | - Andrei Bylinkin
- CIC nanoGUNE BRTA, Tolosa Hiribidea 76, 20018 Donostia-San Sebastián, Spain
| | - Irene Dolado
- CIC nanoGUNE BRTA, Tolosa Hiribidea 76, 20018 Donostia-San Sebastián, Spain
| | - Eli Janzen
- Kansas State University, Tim Taylor Department of Chemical Engineering, Durland Hall, Manhattan, Kansas 66506, United States
| | - James H Edgar
- Kansas State University, Tim Taylor Department of Chemical Engineering, Durland Hall, Manhattan, Kansas 66506, United States
| | - Rainer Hillenbrand
- CIC nanoGUNE BRTA and Department of Electricity and Electronics, UPV/EHU, Tolosa Hiribidea 76, 20018 Donostia-San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, 48009 Bilbao, Spain
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Aminpour H, Eng LM, Kehr SC. Spatially confined vector fields at material-induced resonances in near-field-coupled systems. Opt Express 2020; 28:32316-32330. [PMID: 33114920 DOI: 10.1364/oe.402893] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 09/20/2020] [Indexed: 06/11/2023]
Abstract
Local electric fields play the key role in near-field optical examinations and are especially appealing when exploring heterogeneous or even anisotropic nano-systems. Scattering-type near-field optical microscopy (s-SNOM) is the most commonly used method applied to explore and quantify such confined electric fields at the nanometer length scale: while most works so far did focus on analyzing the z-component oriented perpendicular to the sample surface under p-polarized tip/sample illumination only, recent experimental efforts in s-SNOM report that material resonant excitation might equally allow to probe in-plane electric field components. We thus explore this local vector-field behavior for a simple particle-tip/substrate system by comparing our parametric simulations based on finite element modelling at mid-IR wavelengths, to the standard analytical tip-dipole model. Notably, we analyze all the 4 different combinations for resonant and non-resonant tip and/or sample excitation. Besides the 3-dimensional field confinement under the particle tip present for all scenarios, it is particularly the resonant sample excitations that enable extremely strong field enhancements associated with vector fields pointing along all cartesian coordinates, even without breaking the tip/sample symmetry! In fact, in-plane (s-) resonant sample excitation exceeds the commonly-used p-polarized illumination on non-resonant samples by more than 6 orders of magnitude. Moreover, a variety of different spatial field distributions is found both at and within the sample surface, ranging from electric fields that are oriented strictly perpendicular to the sample surface, to fields that spatially rotate into different directions. Our approach shows that accessing the full vector fields in order to quantify all tensorial properties in nanoscale and modern-type materials lies well within the possibilities and scope of today's s-SNOM technique.
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Lang D, Balaghi L, Winnerl S, Schneider H, Hübner R, Kehr SC, Eng LM, Helm M, Dimakis E, Pashkin A. Nonlinear plasmonic response of doped nanowires observed by infrared nanospectroscopy. Nanotechnology 2019; 30:084003. [PMID: 30523880 DOI: 10.1088/1361-6528/aaf5a7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We report a strong shift of the plasma resonance in highly-doped GaAs/InGaAs core/shell nanowires (NWs) for intense infrared excitation observed by scattering-type scanning near-field infrared microscopy. The studied NWs show a sharp plasma resonance at a photon energy of about 125 meV in the case of continuous wave excitation by a CO2 laser. Probing the same NWs with the pulsed free-electron laser with peak electric field strengths up to several 10 kV cm-1 reveals a power-dependent redshift to about 95 meV and broadening of the plasmonic resonance. We assign this effect to a substantial heating of the electrons in the conduction band and subsequent increase of the effective mass in the nonparabolic Γ-valley.
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Affiliation(s)
- Denny Lang
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, Dresden, Germany. Technische Universität Dresden, Institute of Applied Physics, Dresden, Germany
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9
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Döring J, Lang D, Wehmeier L, Kuschewski F, Nörenberg T, Kehr SC, Eng LM. Low-temperature nanospectroscopy of the structural ferroelectric phases in single-crystalline barium titanate. Nanoscale 2018; 10:18074-18079. [PMID: 30230501 DOI: 10.1039/c8nr04081h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We optically investigate the local-scale ferroelectric domain structure of tetragonal, orthorhombic, and rhombohedral barium titanate (BTO) single crystals using scattering-type scanning near-field infrared (IR) optical microscopy (s-SNIM) at temperatures down to 150 K. Thanks to the precisely tunable narrow-band free-electron laser FELBE, we are able to explore the spectral fingerprints and IR resonances of these three phases and their domain orientations in the optical IR near-field. More clearly, every structural phase is analyzed with respect to its near-field resonances close to a wavelength of 17 μm when exploring the (111)-oriented BTO sample surface. Furthermore, near-field imaging at these resonances is performed, that clearly allows for the unambiguous optical identification of different domain orientations. Since our s-SNIM is based on a non-contact scanning force microscope, our s-SNIM findings are backed up by sample-topography and piezoresponse force microscopy (PFM) imaging, providing complementary information in an excellent match to the s-SNIM results.
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Affiliation(s)
- Jonathan Döring
- Institut für Angewandte Physik, Technische Universität Dresden, Nöthnitzer Str. 61, D-01187 Dresden, Germany.
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Abstract
Light-matter interactions can provide a wealth of detailed information about the structural, electronic, optical, and chemical properties of materials through various excitation and scattering processes that occur over different length, energy, and timescales. Unfortunately, the wavelike nature of light limits the achievable spatial resolution for interrogation and imaging of materials to roughly λ/2 because of diffraction. Scanning near-field optical microscopy (SNOM) breaks this diffraction limit by coupling light to nanostructures that are specifically designed to manipulate, enhance, and/or extract optical signals from very small regions of space. Progress in the SNOM field over the past 30 years has led to the development of many methods to optically characterize materials at lateral spatial resolutions well below 100 nm. We review these exciting developments and demonstrate how SNOM is truly extending optical imaging and spectroscopy to the nanoscale.
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Affiliation(s)
- Richard J. Hermann
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, California 93106, USA;,
| | - Michael J. Gordon
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, California 93106, USA;,
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11
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Hinrichs K, Shaykhutdinov T. Polarization-Dependent Atomic Force Microscopy-Infrared Spectroscopy (AFM-IR): Infrared Nanopolarimetric Analysis of Structure and Anisotropy of Thin Films and Surfaces. Appl Spectrosc 2018; 72:817-832. [PMID: 29652171 DOI: 10.1177/0003702818763604] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Infrared techniques enable nondestructive and label-free studies of thin films with high chemical and structural contrast. In this work, we review recent progress and perspectives in the nanoscale analysis of anisotropic materials using an extended version of the atomic force microscopy-infrared (AFM-IR) technique. This advanced photothermal technique, includes polarization control of the incoming light and bridges the gap in IR spectroscopic analysis of local anisotropic material properties. Such local anisotropy occurs in a wide range of materials during molecular nucleation, aggregation, and crystallization processes. However, analysis of the anisotropy in morphology and structure can be experimentally and theoretically demanding as it is related to order and disorder processes in ranges from nanoscopic to macroscopic length scales, depending on preparation and environmental conditions. In this context IR techniques can significantly assist as IR spectra can be interpreted in the framework of optical models and numerical calculations with respect to both, the present chemical conditions as well as the micro- and nanostructure. With these extraordinary analytic possibilities, the advanced AFM-IR approach is an essential puzzle piece in direction to connect nanoscale and macroscale anisotropic thin film properties experimentally. In this review, we highlight the analytic possibilities of AFM-IR for studies on nanoscale anisotropy with a set of examples for polymer, plasmonic, and polaritonic films, as well as aggregates of large molecules and proteins.
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Affiliation(s)
- Karsten Hinrichs
- Leibniz-Institut für Analytische Wissenschaften-ISAS e.V., Berlin, Germany
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Firkala T, Kuschewski F, Nörenberg T, Klopf J, Pashkin A, Foerstendorf H, Rudolph M, Kehr S, Eng L. Near-Field Optical Examination of Potassium n-Butyl Xanthate/Chalcopyrite Flotation Products. Minerals 2018; 8:118. [DOI: 10.3390/min8030118] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Lang D, Döring J, Nörenberg T, Butykai Á, Kézsmárki I, Schneider H, Winnerl S, Helm M, Kehr SC, Eng LM. Infrared nanoscopy down to liquid helium temperatures. Rev Sci Instrum 2018; 89:033702. [PMID: 29604801 DOI: 10.1063/1.5016281] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
We introduce a scattering-type scanning near-field infrared microscope (s-SNIM) for the local scale near-field sample analysis and spectroscopy from room temperature down to liquid helium (LHe) temperature. The extension of s-SNIM down to T = 5 K is in particular crucial for low-temperature phase transitions, e.g., for the examination of superconductors, as well as low energy excitations. The low temperature (LT) s-SNIM performance is tested with CO2-IR excitation at T = 7 K using a bare Au reference and a structured Si/SiO2-sample. Furthermore, we quantify the impact of local laser heating under the s-SNIM tip apex by monitoring the light-induced ferroelectric-to-paraelectric phase transition of the skyrmion-hosting multiferroic material GaV4S8 at Tc = 42 K. We apply LT s-SNIM to study the spectral response of GaV4S8 and its lateral domain structure in the ferroelectric phase by the mid-IR to THz free-electron laser-light source FELBE at the Helmholtz-Zentrum Dresden-Rossendorf, Germany. Notably, our s-SNIM is based on a non-contact atomic force microscope (AFM) and thus can be complemented in situ by various other AFM techniques, such as topography profiling, piezo-response force microscopy (PFM), and/or Kelvin-probe force microscopy (KPFM). The combination of these methods supports the comprehensive study of the mutual interplay in the topographic, electronic, and optical properties of surfaces from room temperature down to 5 K.
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Affiliation(s)
- Denny Lang
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
| | - Jonathan Döring
- Institute of Applied Physics, Technische Universität Dresden, 01062 Dresden, Germany
| | - Tobias Nörenberg
- Institute of Applied Physics, Technische Universität Dresden, 01062 Dresden, Germany
| | - Ádám Butykai
- Department of Physics, Budapest University of Technology and Economics and MTA-BME Lendület Magneto-Optical Spectroscopy Research Group, 1111 Budapest, Hungary
| | - István Kézsmárki
- Department of Physics, Budapest University of Technology and Economics and MTA-BME Lendület Magneto-Optical Spectroscopy Research Group, 1111 Budapest, Hungary
| | - Harald Schneider
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
| | - Stephan Winnerl
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
| | - Manfred Helm
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
| | - Susanne C Kehr
- Institute of Applied Physics, Technische Universität Dresden, 01062 Dresden, Germany
| | - Lukas M Eng
- Institute of Applied Physics, Technische Universität Dresden, 01062 Dresden, Germany
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Amenabar I, Poly S, Goikoetxea M, Nuansing W, Lasch P, Hillenbrand R. Hyperspectral infrared nanoimaging of organic samples based on Fourier transform infrared nanospectroscopy. Nat Commun 2017; 8:14402. [PMID: 28198384 DOI: 10.1038/ncomms14402] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 12/22/2016] [Indexed: 01/24/2023] Open
Abstract
Infrared nanospectroscopy enables novel possibilities for chemical and structural analysis of nanocomposites, biomaterials or optoelectronic devices. Here we introduce hyperspectral infrared nanoimaging based on Fourier transform infrared nanospectroscopy with a tunable bandwidth-limited laser continuum. We describe the technical implementations and present hyperspectral infrared near-field images of about 5,000 pixel, each one covering the spectral range from 1,000 to 1,900 cm−1. To verify the technique and to demonstrate its application potential, we imaged a three-component polymer blend and a melanin granule in a human hair cross-section, and demonstrate that multivariate data analysis can be applied for extracting spatially resolved chemical information. Particularly, we demonstrate that distribution and chemical interaction between the polymer components can be mapped with a spatial resolution of about 30 nm. We foresee wide application potential of hyperspectral infrared nanoimaging for valuable chemical materials characterization and quality control in various fields ranging from materials sciences to biomedicine. In hyperspectral imaging a broadband spectrum is recorded at each pixel, which creates information-rich images. Here, the authors combine this concept with Fourier transform infrared nanospectroscopy to achieve 5,000-pixel, nanoscale-resolution images at wavelengths between 5 and 10 micrometres.
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15
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Wang H, Wang L, Xu XG. Scattering-type scanning near-field optical microscopy with low-repetition-rate pulsed light source through phase-domain sampling. Nat Commun 2016; 7:13212. [PMID: 27748360 DOI: 10.1038/ncomms13212] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 09/13/2016] [Indexed: 11/15/2022] Open
Abstract
Scattering-type scanning near-field optical microscopy (s-SNOM) allows spectroscopic imaging with spatial resolution below the diffraction limit. With suitable light sources, s-SNOM is instrumental in numerous discoveries at the nanoscale. So far, the light sources have been limited to continuous wave or high-repetition-rate pulsed lasers. Low-repetition-rate pulsed sources cannot be used, due to the limitation of the lock-in detection mechanism that is required for current s-SNOM techniques. Here, we report a near-field signal extraction method that enables low-repetition-rate pulsed light sources. The method correlates scattering signals from pulses with the mechanical phases of the oscillating s-SNOM probe to obtain near-field signal, by-passing the apparent restriction imposed by the Nyquist–Shannon sampling theorem on the repetition rate. The method shall enable s-SNOM with low-repetition-rate pulses with high-peak-powers, such as femtosecond laser amplifiers, to facilitate investigations of strong light–matter interactions and nonlinear processes at the nanoscale. Low repetition rate lasers are suitable for studying nonlinear optical phenomena, while near-field microscopy allows high spatial resolution for nanomaterial characterisation. Here, Wang et al. enable scattering-type near-field microscopy with low repetition rate lasers through phase-domain sampling.
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16
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Muller EA, Pollard B, Bechtel HA, van Blerkom P, Raschke MB. Infrared vibrational nanocrystallography and nanoimaging. Sci Adv 2016; 2:e1601006. [PMID: 27730212 PMCID: PMC5055384 DOI: 10.1126/sciadv.1601006] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 08/18/2016] [Indexed: 05/24/2023]
Abstract
Molecular solids and polymers can form low-symmetry crystal structures that exhibit anisotropic electron and ion mobility in engineered devices or biological systems. The distribution of molecular orientation and disorder then controls the macroscopic material response, yet it is difficult to image with conventional techniques on the nanoscale. We demonstrated a new form of optical nanocrystallography that combines scattering-type scanning near-field optical microscopy with both optical antenna and tip-selective infrared vibrational spectroscopy. From the symmetry-selective probing of molecular bond orientation with nanometer spatial resolution, we determined crystalline phases and orientation in aggregates and films of the organic electronic material perylenetetracarboxylic dianhydride. Mapping disorder within and between individual nanoscale domains, the correlative hybrid imaging of nanoscale heterogeneity provides insight into defect formation and propagation during growth in functional molecular solids.
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Affiliation(s)
- Eric A. Muller
- Department of Physics, Department of Chemistry, and JILA, University of Colorado, Boulder, CO 80309, USA
| | - Benjamin Pollard
- Department of Physics, Department of Chemistry, and JILA, University of Colorado, Boulder, CO 80309, USA
| | - Hans A. Bechtel
- Advanced Light Source Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Peter van Blerkom
- Department of Physics, Department of Chemistry, and JILA, University of Colorado, Boulder, CO 80309, USA
| | - Markus B. Raschke
- Department of Physics, Department of Chemistry, and JILA, University of Colorado, Boulder, CO 80309, USA
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17
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Abstract
Recently, the fundamental and nanoscale understanding of complex phenomena in materials research and the life sciences, witnessed considerable progress. However, elucidating the underlying mechanisms, governed by entangled degrees of freedom such as lattice, spin, orbit, and charge for solids or conformation, electric potentials, and ligands for proteins, has remained challenging. Techniques that allow for distinguishing between different contributions to these processes are hence urgently required. In this paper we demonstrate the application of scattering-type scanning near-field optical microscopy (s-SNOM) as a novel type of nano-probe for tracking transient states of matter. We introduce a sideband-demodulation technique that allows for probing exclusively the stimuli-induced change of near-field optical properties. We exemplify this development by inspecting the decay of an electron-hole plasma generated in SiGe thin films through near-infrared laser pulses. Our approach can universally be applied to optically track ultrafast/-slow processes over the whole spectral range from UV to THz frequencies.
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Affiliation(s)
- F Kuschewski
- Institute of Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - S C Kehr
- Institute of Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - B Green
- Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Ch Bauer
- 1] Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany [2] Department of Physics, Freie Universität Berlin, Berlin, Germany
| | - M Gensch
- Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - L M Eng
- Institute of Applied Physics, Technische Universität Dresden, Dresden, Germany
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18
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Schmidt J, Winnerl S, Seidel W, Bauer C, Gensch M, Schneider H, Helm M. Single-pulse picking at kHz repetition rates using a Ge plasma switch at the free-electron laser FELBE. Rev Sci Instrum 2015; 86:063103. [PMID: 26133824 DOI: 10.1063/1.4921864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We demonstrate a system for picking of mid-infrared and terahertz (THz) radiation pulses from the free-electron laser (FEL) FELBE operating at a repetition rate of 13 MHz. Single pulses are reflected by a dense electron-hole plasma in a Ge slab that is photoexcited by amplified near-infrared (NIR) laser systems operating at repetition rates of 1 kHz and 100 kHz, respectively. The peak intensity of picked pulses is up to 400 times larger than the peak intensity of residual pulses. The required NIR fluence for picking pulses at wavelengths in the range from 5 μm to 30 μm is discussed. In addition, we show that the reflectivity of the plasma decays on a time scale from 100 ps to 1 ns dependent on the wavelengths of the FEL and the NIR laser. The plasma switch enables experiments with the FEL that require high peak power but lower average power. Furthermore, the system is well suited to investigate processes with decay times in the μs to ms regime, i.e., much longer than the 77 ns long pulse repetition period of FELBE.
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Affiliation(s)
- J Schmidt
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden, Germany
| | - S Winnerl
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden, Germany
| | - W Seidel
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden, Germany
| | - C Bauer
- Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden, Germany
| | - M Gensch
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden, Germany
| | - H Schneider
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden, Germany
| | - M Helm
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden, Germany
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19
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Hauer B, Saltzmann T, Simon U, Taubner T. Solvothermally Synthesized Sb2Te3 Platelets Show Unexpected Optical Contrasts in Mid-Infrared Near-Field Scanning Microscopy. Nano Lett 2015; 15:2787-2793. [PMID: 25868047 DOI: 10.1021/nl503697c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We report nanoscale-resolved optical investigations on the local material properties of Sb2Te3 hexagonal platelets grown by solvothermal synthesis. Using mid-infrared near-field microscopy, we find a highly symmetric pattern, which is correlated to a growth spiral and which extends over the entire platelet. As the origin of the optical contrast, we identify domains with different densities of charge carriers. On Sb2Te3 samples grown by other means, we did not find a comparable domain structure.
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Affiliation(s)
- Benedikt Hauer
- †Institute of Physics (IA) and JARA - Fundamentals of Future Information Technologies, RWTH Aachen University, 52056 Aachen, Germany
| | - Tobias Saltzmann
- ‡Institute of Inorganic Chemistry (IAC) and JARA - Fundamentals of Future Information Technologies, RWTH Aachen University, 52056 Aachen, Germany
| | - Ulrich Simon
- ‡Institute of Inorganic Chemistry (IAC) and JARA - Fundamentals of Future Information Technologies, RWTH Aachen University, 52056 Aachen, Germany
| | - Thomas Taubner
- †Institute of Physics (IA) and JARA - Fundamentals of Future Information Technologies, RWTH Aachen University, 52056 Aachen, Germany
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20
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Fehrenbacher M, Winnerl S, Schneider H, Döring J, Kehr SC, Eng LM, Huo Y, Schmidt OG, Yao K, Liu Y, Helm M. Plasmonic superlensing in doped GaAs. Nano Lett 2015; 15:1057-61. [PMID: 25584806 DOI: 10.1021/nl503996q] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
We demonstrate a semiconductor based broadband near-field superlens in the mid-infrared regime. Here, the Drude response of a highly doped n-GaAs layer induces a resonant enhancement of evanescent waves accompanied by a significantly improved spatial resolution at radiation wavelengths around λ = 20 μm, adjustable by changing the doping concentration. In our experiments, gold stripes below the GaAs superlens are imaged with a λ/6 subwavelength resolution by an apertureless near-field optical microscope utilizing infrared radiation from a free-electron laser. The resonant behavior of the observed superlensing effect is in excellent agreement with simulations based on the Drude-Lorentz model. Our results demonstrate a rather simple superlens implementation for infrared nanospectroscopy.
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Affiliation(s)
- Markus Fehrenbacher
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , Bautzner Landstraße 400, 01328 Dresden, Germany
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21
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Bensmann S, Gaußmann F, Lewin M, Wüppen J, Nyga S, Janzen C, Jungbluth B, Taubner T. Near-field imaging and spectroscopy of locally strained GaN using an IR broadband laser. Opt Express 2014; 22:22369-22381. [PMID: 25321708 DOI: 10.1364/oe.22.022369] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Scattering-type scanning near-field optical microscopy (SNOM) offers the possibility to analyze material properties like strain in crystals at the nanoscale. In this paper we introduce a SNOM setup employing a newly developed tunable broadband laser source with a covered spectral range from 9 µm to 16 µm. This setup allows for the first time optical analyses of the crystal structure of gallium nitride (GaN) at the nanometer scale by excitation of a near-field phonon resonance around 14.5 µm. On the example of an artificially induced stress field within a GaN wafer, we present a method for a 2D visualization of small deviations in the crystal structure, which allows for fast qualitative characterizations. Subsequently, the stress levels at chosen points were quantified by recording complex near-field spectra and correlating them with theoretical model calculations. Applied to the cross-section of a heteroepitaxially grown GaN wafer, we finally demonstrate the capability of our setup to analyze the relaxation of the crystal structure along the growth axis with a nanometer spatial resolution.
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22
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Hermann P, Hoehl A, Ulrich G, Fleischmann C, Hermelink A, Kästner B, Patoka P, Hornemann A, Beckhoff B, Rühl E, Ulm G. Characterization of semiconductor materials using synchrotron radiation-based near-field infrared microscopy and nano-FTIR spectroscopy. Opt Express 2014; 22:17948-58. [PMID: 25089414 DOI: 10.1364/oe.22.017948] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We describe the application of scattering-type near-field optical microscopy to characterize various semiconducting materials using the electron storage ring Metrology Light Source (MLS) as a broadband synchrotron radiation source. For verifying high-resolution imaging and nano-FTIR spectroscopy we performed scans across nanoscale Si-based surface structures. The obtained results demonstrate that a spatial resolution below 40 nm can be achieved, despite the use of a radiation source with an extremely broad emission spectrum. This approach allows not only for the collection of optical information but also enables the acquisition of near-field spectral data in the mid-infrared range. The high sensitivity for spectroscopic material discrimination using synchrotron radiation is presented by recording near-field spectra from thin films composed of different materials used in semiconductor technology, such as SiO2, SiC, SixNy, and TiO2.
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23
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Stiegler JM, Tena-Zaera R, Idigoras O, Chuvilin A, Hillenbrand R. Correlative infrared-electron nanoscopy reveals the local structure-conductivity relationship in zinc oxide nanowires. Nat Commun 2012; 3:1131. [PMID: 23072801 DOI: 10.1038/ncomms2118] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 09/05/2012] [Indexed: 11/08/2022] Open
Abstract
High-resolution characterization methods play a key role in the development, analysis and optimization of nanoscale materials and devices. Because of the various material properties, only a combination of different characterization techniques provides a comprehensive understanding of complex functional materials. Here we introduce correlative infrared–electron nanoscopy, a novel method yielding transmission electron microscope and infrared near-field images of one and the same nanostructure. While transmission electron microscopy provides structural information up to the atomic level, infrared near-field imaging yields nanoscale maps of chemical composition and conductivity. We demonstrate the method's potential by studying the relation between conductivity and crystal structure in ZnO nanowire cross-sections. The combination of infrared conductivity maps and the local crystal structure reveals a radial free-carrier gradient, which inversely correlates to the density of extended crystalline defects. Our method opens new avenues for studying the local interplay between structure, conductivity and chemical composition in widely different material systems. High-resolution characterisation techniques enable us to better understand the properties of nanoscale materials and devices. By combining electron microscopy and infrared nanoscopy, Stiegler et al. demonstrate a general approach to simultaneously probe the structural, chemical and electronic properties of a nanostructure.
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24
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Hermann P, Hoehl A, Patoka P, Huth F, Rühl E, Ulm G. Near-field imaging and nano-Fourier-transform infrared spectroscopy using broadband synchrotron radiation. Opt Express 2013; 21:2913-9. [PMID: 23481749 DOI: 10.1364/oe.21.002913] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We demonstrate scanning near-field optical microscopy with a spatial resolution below 100 nm by using low intensity broadband synchrotron radiation in the IR regime. The use of such a broadband radiation source opens up the possibility to perform nano-Fourier-transform infrared spectroscopy over a wide spectral range.
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Affiliation(s)
- Peter Hermann
- Physikalisch-Technische Bundesanstalt (PTB), Abbestrasse 2-12, 10587 Berlin, Germany.
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25
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Jacob R, Winnerl S, Fehrenbacher M, Bhattacharyya J, Schneider H, Wenzel MT, Ribbeck HGV, Eng LM, Atkinson P, Schmidt OG, Helm M. Intersublevel spectroscopy on single InAs-quantum dots by terahertz near-field microscopy. Nano Lett 2012; 12:4336-4340. [PMID: 22775149 DOI: 10.1021/nl302078w] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Using scattering-type near-field infrared microscopy in combination with a free-electron laser, intersublevel transitions in buried single InAs quantum dots are investigated. The experiments are performed at room temperature on doped self-assembled quantum dots capped with a 70 nm GaAs layer. Clear near-field contrast of single dots is observed when the photon energy of the incident beam matches intersublevel transition energies, namely the p-d and s-d transition of conduction band electrons confined in the dots. The observed room-temperature line width of 5-8 meV of these resonances in the mid-infrared range is significantly below the inhomogeneously broadened spectral lines of quantum dot ensembles. The experiment highlights the strength of near-field microspectroscopy by demonstrating signals from bound-to-bound transitions of single electrons in a probe volume of the order of (100 nm)(3).
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Affiliation(s)
- Rainer Jacob
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, P.O. Box 51 01 19, 01314 Dresden, Germany
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26
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Bousseksou A, Babuty A, Tetienne JP, Moldovan-Doyen I, Braive R, Beaudoin G, Sagnes I, De Wilde Y, Colombelli R. Sub-wavelength energy concentration with electrically generated mid-infrared surface plasmons. Opt Express 2012; 20:13738-13747. [PMID: 22714439 DOI: 10.1364/oe.20.013738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
While freely propagating photons cannot be focused below their diffraction limit, surface-plasmon polaritons follow the metallic surface to which they are bound, and can lead to extremely sub-wavelength energy volumes. These properties are lost at long mid-infrared and THz wavelengths where metals behave as quasi-perfect conductors, but can in principle be recovered by artificially tailoring the surface-plasmon dispersion. We demonstrate - in the important mid-infrared range of the electromagnetic spectrum - the generation onto a semiconductor chip of plasmonic excitations which can travel along long distances, on bent paths, to be finally focused into a sub-wavelength volume. The demonstration of these advanced functionalities is supported by full near-field characterizations of the electromagnetic field distribution on the surface of the active plasmonic device.
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Affiliation(s)
- A Bousseksou
- Institut d’Electronique Fondamentale, Univ. Paris Sud, UMR8622 CNRS, 91405 Orsay, France.
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27
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Ishikawa M, Katsura M, Nakashima S, Ikemoto Y, Okamura H. Broadband near-field mid-infrared spectroscopy and application to phonon resonances in quartz. Opt Express 2012; 20:11064-11072. [PMID: 22565729 DOI: 10.1364/oe.20.011064] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Infrared (IR) spectroscopy is a versatile analytical method and nano-scale spatial resolution could be achieved by scattering type near-field optical microscopy (s-SNOM). The spectral bandwidth was, however, limited to approximately 300 cm(-1) with a laser light source. In the present study, the development of a broadband mid-IR near-field spectroscopy with a ceramic light source is demonstrated. A much wider bandwidth (at least 3000 to 1000 cm(-1)) is achieved with a ceramic light source. The experimental data on quartz Si-O phonon resonance bands are well reproduced by theoretical simulations indicating the validity of the present broadband near-field IR spectroscopy.
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Affiliation(s)
- Michio Ishikawa
- Department of Earth and Space Science, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan.
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28
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Lee WM, Sung JH, Chu K, Moya X, Lee D, Kim CJ, Mathur ND, Cheong SW, Yang CH, Jo MH. Spatially resolved photodetection in leaky ferroelectric BiFeO(3). Adv Mater 2012; 24:OP49-OP53. [PMID: 22282134 DOI: 10.1002/adma.201102816] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Indexed: 05/31/2023]
Abstract
Potential gradients due to the spontaneous polarization of BiFeO(3) yield asymmetric and nonlinear photocarrier dynamics. Photocurrent direction is determined by local ferroelectric domain orientation, whereas magnitude is spectrally centered around charged domain walls that are associated with oxygen vacancy migration. Photodetection can be electrically controlled by manipulating ferroelectric domain configurations.
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Affiliation(s)
- Won-Mo Lee
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang, Gyungbuk, Korea
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29
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Stiegler JM, Abate Y, Cvitkovic A, Romanyuk YE, Huber AJ, Leone SR, Hillenbrand R. Nanoscale infrared absorption spectroscopy of individual nanoparticles enabled by scattering-type near-field microscopy. ACS Nano 2011; 5:6494-6499. [PMID: 21770439 DOI: 10.1021/nn2017638] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Infrared absorption spectroscopy is a powerful and widely used tool for analyzing the chemical composition and structure of materials. Because of the diffraction limit, however, it cannot be applied for studying individual nanostructures. Here we demonstrate that the phase contrast in substrate-enhanced scattering-type scanning near-field optical microscopy (s-SNOM) provides a map of the infrared absorption spectrum of individual nanoparticles with nanometer-scale spatial resolution. We succeeded in the chemical identification of silicon nitride nanoislands with heights well below 10 nm, by infrared near-field fingerprint spectroscopy of the Si-N stretching bond. Employing a novel theoretical model, we show that the near-field phase spectra of small particles correlate well with their far-field absorption spectra. On the other hand, the spectral near-field contrast does not scale with the volume of the particles. We find a nearly linear scaling law, which we can attribute to the near-field coupling between the near-field probe and the substrate. Our results provide fundamental insights into the spectral near-field contrast of nanoparticles and clearly demonstrate the capability of s-SNOM for nanoscale chemical mapping based on local infrared absorption.
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Kehr SC, Liu YM, Martin LW, Yu P, Gajek M, Yang SY, Yang CH, Wenzel MT, Jacob R, von Ribbeck HG, Helm M, Zhang X, Eng LM, Ramesh R. Near-field examination of perovskite-based superlenses and superlens-enhanced probe-object coupling. Nat Commun 2011; 2:249. [PMID: 21427720 DOI: 10.1038/ncomms1249] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Accepted: 02/22/2011] [Indexed: 11/08/2022] Open
Abstract
A planar slab of negative-index material works as a superlens with sub-diffraction-limited resolution, as propagating waves are focused and, moreover, evanescent waves are reconstructed in the image plane. Here we demonstrate a superlens for electric evanescent fields with low losses using perovskites in the mid-infrared regime. The combination of near-field microscopy with a tunable free-electron laser allows us to address precisely the polariton modes, which are critical for super-resolution imaging. We spectrally study the lateral and vertical distributions of evanescent waves around the image plane of such a lens, and achieve imaging resolution of λ/14 at the superlensing wavelength. Interestingly, at certain distances between the probe and sample surface, we observe a maximum of these evanescent fields. Comparisons with numerical simulations indicate that this maximum originates from an enhanced coupling between probe and object, which might be applicable for multifunctional circuits, infrared spectroscopy and thermal sensors.
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Huth F, Schnell M, Wittborn J, Ocelic N, Hillenbrand R. Infrared-spectroscopic nanoimaging with a thermal source. Nat Mater 2011; 10:352-6. [PMID: 21499314 DOI: 10.1038/nmat3006] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Accepted: 03/08/2011] [Indexed: 05/22/2023]
Abstract
Fourier-transform infrared (FTIR) spectroscopy is a widely used analytical tool for chemical identification of inorganic, organic and biomedical materials, as well as for exploring conduction phenomena. Because of the diffraction limit, however, conventional FTIR cannot be applied for nanoscale imaging. Here we demonstrate a novel FTIR system that allows for infrared-spectroscopic nanoimaging of dielectric properties (nano-FTIR). Based on superfocusing of thermal radiation with an infrared antenna, detection of the scattered light, and strong signal enhancement employing an asymmetric FTIR spectrometer, we improve the spatial resolution of conventional infrared spectroscopy by more than two orders of magnitude. By mapping a semiconductor device, we demonstrate spectroscopic identification of silicon oxides and quantification of the free-carrier concentration in doped Si regions with a spatial resolution better than 100 nm. We envisage nano-FTIR becoming a powerful tool for chemical identification of nanomaterials, as well as for quantitative and contact-free measurement of the local free-carrier concentration and mobility in doped nanostructures.
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Affiliation(s)
- F Huth
- Nanooptics Group, CIC nanoGUNE Consolider, 20018 Donostia-San Sebastián, Spain
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32
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Jacob R, Winnerl S, Schneider H, Helm M, Wenzel MT, von Ribbeck HG, Eng LM, Kehr SC. Quantitative determination of the charge carrier concentration of ion implanted silicon by IR-near-field spectroscopy. Opt Express 2010; 18:26206-26213. [PMID: 21164970 DOI: 10.1364/oe.18.026206] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We use a combination of a scattering-type near-field infrared microscope with a free-electron laser as an intense, tunable radiation source to spatially and spectrally resolve buried doped layers in silicon. To this end, boron implanted stripes in silicon are raster scanned at different wavelengths in the range from 10 to 14 µm. An analysis based on a simple Drude model for the dielectric function of the sample yields quantitatively correct values for the concentration of the activated carriers. In a control experiment at the fixed wavelength of 10.6 µm, interferometric near-field signals are recorded. The phase information gained in this experiment is fully consistent with the carrier concentration obtained in the spectrally resolved experiments.
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Affiliation(s)
- Rainer Jacob
- Institute of Ion Beam Physics and Materials Research, Forschungszentrum Dresden-Rossendorf, PO Box 51 01 19, 01314 Dresden, Germany.
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Abstract
We demonstrate the application of scattering-type scanning near-field optical microscopy (s-SNOM) for infrared (IR) spectroscopic material recognition in state-of-the-art semiconductor devices. In particular, we employ s-SNOM for imaging of industrial CMOS transistors with a resolution better than 20 nm, which allows for the first time IR spectroscopic recognition of amorphous SiO(2) and Si(3)N(4) components in a single transistor device. The experimentally recorded near-field spectral signature of amorphous SiO(2) shows excellent agreement with model calculations based on literature dielectric values, verifying that the characteristic near-field contrasts of SiO(2) stem from a phonon-polariton resonant near-field interaction between the probing tip and the SiO(2) nanostructures. Local material recognition by s-SNOM in combination with its capabilities of contact-free and non-invasive conductivity- and strain-mapping makes IR near-field microscopy a versatile metrology technique for nanoscale material characterization and semiconductor device analysis with application potential in research and development, failure analysis and reverse engineering.
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Affiliation(s)
- A J Huber
- Nanooptics Group, CIC nanoGUNE Consolider, E-20018 Donostia, San Sebastian, Spain
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Abstract
This review outlines progress in atomic force infrared microscopy, reviewing the methodology and its application in nanoscale infrared absorption imaging of both biological and functional materials, including an outline of where this emerging method has been applied to image cellular systems in aqueous environments.
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Affiliation(s)
- James H Rice
- School of Physics, University College Dublin, Belfield, Dublin, Ireland.
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35
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Gigler AM, Huber AJ, Bauer M, Ziegler A, Hillenbrand R, Stark RW. Nanoscale residual stress-field mappingaround nanoindents in SiCby IR s-SNOM and confocal Raman microscopy. Opt Express 2009; 17:22351-22357. [PMID: 20052158 DOI: 10.1364/oe.17.022351] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We map a nanoindent in a silicon carbide (SiC) crystal by infrared (IR) scattering-type scanning near-field optical microscopy (s-SNOM) and confocal Raman microscopy and interpret the resulting images in terms of local residual stress-fields. By comparing near-field IR and confocal Raman images, we find that the stress-induced shifts of the longitudinal optical phonon-frequencies (LO) and the related shift of the phonon-polariton near-field resonance give rise to Raman and s-SNOM image contrasts, respectively. We apply single-frequency IR s-SNOM for nanoscale resolved imaging of local stress-fields and confocal Raman microscopy to obtain the complete spectral information about stress-induced shifts of the phonon frequencies at diffraction limited spatial resolution. The spatial extension of the local stress-field around the nanoindent agrees well between both techniques. Our results demonstrate that both methods ideally complement each other, allowing for the detailed analysis of stress-fields at e.g. material and grain boundaries, in Micro-Electro-Mechanical-Systems (MEMS), or in engineered nanostructures.
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Affiliation(s)
- Alexander M Gigler
- Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universität München, Theresienstr. 41, 80333 Munich, Germany.
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36
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Berweger S, Neacsu CC, Mao Y, Zhou H, Wong SS, Raschke MB. Optical nanocrystallography with tip-enhanced phonon Raman spectroscopy. Nat Nanotechnol 2009; 4:496-9. [PMID: 19662010 DOI: 10.1038/nnano.2009.190] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2008] [Accepted: 06/19/2009] [Indexed: 05/11/2023]
Abstract
Conventional phonon Raman spectroscopy is a powerful experimental technique for the study of crystalline solids that allows crystallography, phase and domain identification on length scales down to approximately 1 microm. Here we demonstrate the extension of tip-enhanced Raman spectroscopy to optical crystallography on the nanoscale by identifying intrinsic ferroelectric domains of individual BaTiO(3) nanocrystals through selective probing of different transverse optical phonon modes in the system. The technique is generally applicable for most crystal classes, and for example, structural inhomogeneities, phase transitions, ferroic order and related finite-size effects occurring on nanometre length scales can be studied with simultaneous symmetry selectivity, nanoscale sensitivity and chemical specificity.
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Affiliation(s)
- Samuel Berweger
- Department of Chemistry and Department of Physics, University of Washington, Seattle, WA 98195, USA
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37
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Zvyagin SA, Ozerov M, Cizmár E, Kamenskyi D, Zherlitsyn S, Herrmannsdörfer T, Wosnitza J, Wünsch R, Seidel W. Terahertz-range free-electron laser electron spin resonance spectroscopy: techniques and applications in high magnetic fields. Rev Sci Instrum 2009; 80:073102. [PMID: 19655938 DOI: 10.1063/1.3155509] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The successful use of picosecond-pulse free-electron-laser (FEL) radiation for the continuous-wave terahertz-range electron spin resonance (ESR) spectroscopy has been demonstrated. The combination of two linac-based FELs (covering the wavelength range of 4-250 microm) with pulsed magnetic fields up to 70 T allows for multifrequency ESR spectroscopy in a frequency range of 1.2-75 THz with a spectral resolution better than 1%. The performance of the spectrometer is illustrated with ESR spectra obtained in the 2,2-diphenyl-1-picrylhydrazyl and the low-dimensional organic material (C6H9N2)CuCl3.
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Affiliation(s)
- S A Zvyagin
- Dresden High Magnetic Field Laboratory (HLD), Forschungszentrum Dresden-Rossendorf (FZD), 01314 Dresden, Germany.
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38
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Huber AJ, Ziegler A, Köck T, Hillenbrand R. Infrared nanoscopy of strained semiconductors. Nat Nanotechnol 2009; 4:153-7. [PMID: 19265843 DOI: 10.1038/nnano.2008.399] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Accepted: 12/03/2008] [Indexed: 05/22/2023]
Abstract
Knowledge about strain at the nanometre scale is essential for tailoring the mechanical and electronic properties of materials. Flaws, cracks and their local strain fields can be detrimental to the structural integrity of many solids. Conversely, the controlled straining of silicon can be used to improve the performance of electronic devices. Here, we demonstrate that infrared near-field microscopy allows direct, non-invasive mapping and a semiquantitative analysis of residual strain fields in polar semiconductor crystals with nanometre-scale resolution. Our experiments with silicon carbide crystals yield optical images of nanoindents showing strain features as small as 50 nm and the evolution of nanocracks. In addition, by imaging nanoindents in doped silicon, we provide experimental evidence for plasmon-assisted near-field imaging of free-carrier properties in nanoscale strain fields. Near-field infrared strain mapping provides possibilities for nanoscale material and device characterization, and could become a tool for nanoscale mapping of the local free-carrier mobility in strain-engineered semiconductors.
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Affiliation(s)
- A J Huber
- Nanooptics Laboratory, CIC nanoGUNE Consolider, 20018 Donostia-San Sebastian, Spain
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Wenzel MT, Härtling T, Olk P, Kehr SC, Grafström S, Winnerl S, Helm M, Eng LM. Gold nanoparticle tips for optical field confinement in infrared scattering near-field optical microscopy. Opt Express 2008; 16:12302-12312. [PMID: 18679508 DOI: 10.1364/oe.16.012302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We report on the implementation of metal nanoparticles as probes for scattering and apertureless near-field optical investigations in the mid-infrared (mid-IR) spectral regime. At these wavelengths, an efficient electric-field confinement is necessary and achieved here through a gold metal nanoparticle of 80 nm in diameter (Au80-MNP) acting as the optical antenna. The Au80-MNP is attached to a standard AFM cantilever used as the spatial manipulator. When approached to a sample surface while being illuminated with an infrared beam, the Au80-MNP produces a considerably improved spatial confinement of the electric field compared to an ordinary scattering AFM tip. We demonstrate here the confinement normal to the sample surface by making use of a sample-induced phonon polariton resonance in a ferroelectric lithium niobate sample. Our experimental findings are in very good agreement with the quasistatic dipole model and show improved optical resolution via well-selected antenna particles.
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Affiliation(s)
- Marc Tobias Wenzel
- Institute of Applied Photophysics, Technische Universität Dresden, 01062 Dresden, Germany.
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