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Chen X, Reichardt S, Lin ML, Leng YC, Lu Y, Wu H, Mei R, Wirtz L, Zhang X, Ferrari AC, Tan PH. Control of Raman Scattering Quantum Interference Pathways in Graphene. ACS NANO 2023; 17:5956-5962. [PMID: 36897053 PMCID: PMC10062028 DOI: 10.1021/acsnano.3c00180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 02/24/2023] [Indexed: 06/18/2023]
Abstract
Graphene is an ideal platform to study the coherence of quantum interference pathways by tuning doping or laser excitation energy. The latter produces a Raman excitation profile that provides direct insight into the lifetimes of intermediate electronic excitations and, therefore, on quantum interference, which has so far remained elusive. Here, we control the Raman scattering pathways by tuning the laser excitation energy in graphene doped up to 1.05 eV. The Raman excitation profile of the G mode indicates its position and full width at half-maximum are linearly dependent on doping. Doping-enhanced electron-electron interactions dominate the lifetimes of Raman scattering pathways and reduce Raman interference. This will provide guidance for engineering quantum pathways for doped graphene, nanotubes, and topological insulators.
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Affiliation(s)
- Xue Chen
- State
Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center
of Materials Science and Optoelectronics Engineering and CAS Center
of Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Sven Reichardt
- Department
of Physics and Materials Science, University
of Luxembourg, Luxembourg 1511, Luxembourg
| | - Miao-Ling Lin
- State
Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
| | - Yu-Chen Leng
- State
Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
| | - Yan Lu
- State
Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
| | - Heng Wu
- State
Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center
of Materials Science and Optoelectronics Engineering and CAS Center
of Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rui Mei
- State
Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center
of Materials Science and Optoelectronics Engineering and CAS Center
of Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ludger Wirtz
- Department
of Physics and Materials Science, University
of Luxembourg, Luxembourg 1511, Luxembourg
| | - Xin Zhang
- State
Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center
of Materials Science and Optoelectronics Engineering and CAS Center
of Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Andrea C. Ferrari
- Cambridge
Graphene Centre, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, United Kingdom
| | - Ping-Heng Tan
- State
Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center
of Materials Science and Optoelectronics Engineering and CAS Center
of Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing 100049, China
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2
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Reichardt S, Wirtz L. Nonadiabatic exciton-phonon coupling in Raman spectroscopy of layered materials. SCIENCE ADVANCES 2020; 6:eabb5915. [PMID: 32821840 PMCID: PMC7413722 DOI: 10.1126/sciadv.abb5915] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 06/26/2020] [Indexed: 05/25/2023]
Abstract
We present an ab initio computational approach for the calculation of resonant Raman intensities, including both excitonic and nonadiabatic effects. Our diagrammatic approach, which we apply to two prototype, semiconducting layered materials, allows a detailed analysis of the impact of phonon-mediated exciton-exciton scattering on the intensities. In the case of bulk hexagonal boron nitride, this scattering leads to strong quantum interference between different excitonic resonances, strongly redistributing oscillator strength with respect to optical absorption spectra. In the case of MoS2, we observe that quantum interference effects are suppressed by the spin-orbit splitting of the excitons.
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3
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Abstract
We measured a 2D peak line shape of epitaxial graphene grown on SiC in high vacuum, argon and graphene prepared by hydrogen intercalation from the so called buffer layer on a silicon face of SiC. We fitted the 2D peaks by Lorentzian and Voigt line shapes. The detailed analysis revealed that the Voigt line shape describes the 2D peak line shape better. We have determined the contribution of the homogeneous and inhomogeneous broadening. The homogeneous broadening is attributed to the intrinsic lifetime. Although the inhomogeneous broadening can be attributed to the spatial variations of the charge density, strain and overgrown graphene ribbons on the sub-micrometer length scales, we found dominant contribution of the strain fluctuations. The quasi free-standing graphene grown by hydrogen intercalation is shown to have the narrowest linewidth due to both homogeneous and inhomogeneous broadening.
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4
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Pardanaud C, Merlen A, Gratzer K, Chuzel O, Nikolaievskyi D, Patrone L, Clair S, Ramirez-Jimenez R, de Andrés A, Roubin P, Parrain JL. Forming Weakly Interacting Multilayers of Graphene Using Atomic Force Microscope Tip Scanning and Evidence of Competition between Inner and Outer Raman Scattering Processes Piloted by Structural Defects. J Phys Chem Lett 2019; 10:3571-3579. [PMID: 31198044 DOI: 10.1021/acs.jpclett.9b00564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We report on an alternative route based on nanomechanical folding induced by an AFM tip to obtain weakly interacting multilayer graphene (wi-MLG) from a chemical vapor deposition (CVD)-grown single-layer graphene (SLG). The tip first cuts and then pushes and folds graphene during zigzag movements. The pushed graphene has been analyzed using various Raman microscopy plots- AD/ AG × EL4 vs ΓG, ω2D vs Γ2D, Γ2D vs ΓG, ω2D+/- vs Γ2D+/-, and A2D-/ A2D+ vs A2D/ AG. We show that the SLG in-plane properties are maintained under the folding process and that a few tens of graphene layers are stacked, with a limited number of structural defects. A blue shift of about 20 cm-1 of the 2D band is observed. The relative intensity of the 2D- and 2D+ bands have been related to structural defects, giving evidence of their role in the inner and outer processes at play close to the Dirac cone.
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Affiliation(s)
- C Pardanaud
- Aix Marseille Univ , CNRS, PIIM , Marseille , France
| | - A Merlen
- Aix Marseille Univ, Université de Toulon , CNRS, IM2NP , Marseille , France
| | - K Gratzer
- Aix Marseille Univ , CNRS, Centrale Marseille, iSm2 , Marseille , France
| | - O Chuzel
- Aix Marseille Univ , CNRS, Centrale Marseille, iSm2 , Marseille , France
| | - D Nikolaievskyi
- Aix Marseille Univ , CNRS, PIIM , Marseille , France
- Aix Marseille Univ , CNRS, Centrale Marseille, iSm2 , Marseille , France
| | - L Patrone
- Aix Marseille Univ, Université de Toulon , CNRS, IM2NP , Marseille , France
- ISEN Yncréa Méditerranée , CNRS, IM2NP UMR 7334 , Toulon , France
| | - S Clair
- Aix Marseille Univ, Université de Toulon , CNRS, IM2NP , Marseille , France
| | - R Ramirez-Jimenez
- Departamento de Física, Escuela Politecnica Superior , Universidad Carlos III de Madrid , Avenida Universidad 30 , Leganes, 28911 Madrid , Spain
- Instituto de Ciencia de Materiales de Madrid , Consejo Superior de Investigaciones Científicas , Cantoblanco, 28049 Madrid , Spain
| | - A de Andrés
- Instituto de Ciencia de Materiales de Madrid , Consejo Superior de Investigaciones Científicas , Cantoblanco, 28049 Madrid , Spain
| | - P Roubin
- Aix Marseille Univ , CNRS, PIIM , Marseille , France
| | - J-L Parrain
- Aix Marseille Univ , CNRS, Centrale Marseille, iSm2 , Marseille , France
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Li M, Zhang T, Wang P, Li M, Wang J, Liu Z. Temperature Characteristics of a Pressure Sensor Based on BN/Graphene/BN Heterostructure. SENSORS 2019; 19:s19102223. [PMID: 31091736 PMCID: PMC6567352 DOI: 10.3390/s19102223] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 05/08/2019] [Accepted: 05/09/2019] [Indexed: 11/16/2022]
Abstract
Temperature is a significant factor in the application of graphene-based pressure sensors. The influence of temperature on graphene pressure sensors is twofold: an increase in temperature causes the substrates of graphene pressure sensors to thermally expand, and thus, the graphene membrane is stretched, leading to an increase in the device resistance; an increase in temperature also causes a change in the graphene electrophonon coupling, resulting in a decrease in device resistance. To investigate which effect dominates the influence of temperature on the pressure sensor based on the graphene–boron nitride (BN) heterostructure proposed in our previous work, the temperature characteristics of two BN/graphene/BN heterostructures with and without a microcavity beneath them were analyzed in the temperature range 30–150 °C. Experimental results showed that the resistance of the BN/graphene/BN heterostructure with a microcavity increased with the increase in temperature, and the temperature coefficient was up to 0.25%°C−1, indicating the considerable influence of thermal expansion in such devices. In contrast, with an increase in temperature, the resistance of the BN/graphene/BN heterostructure without a microcavity decreased with a temperature coefficient of −0.16%°C−1. The linearity of the resistance change rate (ΔR/R)–temperature curve of the BN/graphene/BN heterostructure without a microcavity was better than that of the BN/graphene/BN heterostructure with a microcavity. These results indicate that the influence of temperature on the pressure sensors based on BN/graphene/BN heterostructures should be considered, especially for devices with pressure microcavities. BN/graphene/BN heterostructures without microcavities can be used as high-performance temperature sensors.
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Affiliation(s)
- Mengwei Li
- Key Laboratory of Instrument Science & Dynamic Measurement, North University of China, Taiyuan 030051, China.
- North University of China, Academy for Advanced Interdisciplinary Research, Taiyuan 030051, China.
- Institute of Microelectronics, Tsinghua University, Beijing 100084, China.
| | - Teng Zhang
- Key Laboratory of Instrument Science & Dynamic Measurement, North University of China, Taiyuan 030051, China.
| | - Pengcheng Wang
- Key Laboratory of Instrument Science & Dynamic Measurement, North University of China, Taiyuan 030051, China.
| | - Minghao Li
- Key Laboratory of Instrument Science & Dynamic Measurement, North University of China, Taiyuan 030051, China.
| | - Junqiang Wang
- Microsystem Integration Center, North University of China, Taiyuan 030051, China.
| | - Zewen Liu
- Institute of Microelectronics, Tsinghua University, Beijing 100084, China.
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6
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Hu KM, Xue ZY, Liu YQ, Long H, Peng B, Yan H, Di ZF, Wang X, Lin L, Zhang WM. Tension-Induced Raman Enhancement of Graphene Membranes in the Stretched State. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2019; 15:e1804337. [PMID: 30506848 DOI: 10.1002/smll.201804337] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 11/14/2018] [Indexed: 06/09/2023]
Abstract
The intensity ratio of the 2D band to the G band, I2D /IG , is a good criterion in selecting high quality monolayer graphene samples; however, the evaluation of the ultimate value of I2D /IG for intrinsic monolayer graphene is a challenging yet interesting issue. Here, an interesting tension-induced Raman enhancement phenomenon is reported in supported graphene membranes, which show a transition from the corrugated state to the stretched state in the vicinity of wells. The I2D /IG of substrate-supported graphene membranes near wells are significantly enhanced up to 16.74, which is the highest experimental value to the best of knowledge, increasing by more than 600% when the testing points approach the well edges.The macroscopic origin of this phenomenon is that corrugated graphene membranes are stretched by built-in tensions. A lattice dynamic model is proposed to successfully reveal the microscopic mechanism of this phenomenon. The theoretical results agree well with the experimental data, demonstrating that tensile stresses can depress the amplitude of in-plane vibration of sp2 -bonded carbon atoms and result in the decrease in the G band intensity. This work can be helpful in furthering the development of the method of suppressing small ripples in graphene and acquiring ultraflat 2D materials.
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Affiliation(s)
- Kai-Ming Hu
- State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Zhong-Ying Xue
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, China
| | - Yun-Qi Liu
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, China
| | - Hu Long
- Department of Physics, University of California at Berkeley, Berkeley, CA, 94720, USA
| | - Bo Peng
- State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Han Yan
- State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Zeng-Feng Di
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, China
| | - Xi Wang
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, China
| | - Liwei Lin
- Berkeley Sensor and Actuator Center, University of California at Berkeley, 5101-B Etcheverry, Berkeley, CA, 94720-1774, USA
| | - Wen-Ming Zhang
- State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
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Hell MG, Ehlen N, Senkovskiy BV, Hasdeo EH, Fedorov A, Dombrowski D, Busse C, Michely T, di Santo G, Petaccia L, Saito R, Grüneis A. Resonance Raman Spectrum of Doped Epitaxial Graphene at the Lifshitz Transition. NANO LETTERS 2018; 18:6045-6056. [PMID: 30157652 DOI: 10.1021/acs.nanolett.8b02979] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We employ ultra-high vacuum (UHV) Raman spectroscopy in tandem with angle-resolved photoemission (ARPES) to investigate the doping-dependent Raman spectrum of epitaxial graphene on Ir(111). The evolution of Raman spectra from pristine to heavily Cs doped graphene up to a carrier concentration of 4.4 × 1014 cm-2 is investigated. At this doping, graphene is at the onset of the Lifshitz transition and renormalization effects reduce the electronic bandwidth. The optical transition at the saddle point in the Brillouin zone then becomes experimentally accessible by ultraviolet (UV) light excitation, which achieves resonance Raman conditions in close vicinity to the van Hove singularity in the joint density of states. The position of the Raman G band of fully doped graphene/Ir(111) shifts down by ∼60 cm-1. The G band asymmetry of Cs doped epitaxial graphene assumes an unusual strong Fano asymmetry opposite to that of the G band of doped graphene on insulators. Our calculations can fully explain these observations by substrate dependent quantum interference effects in the scattering pathways for vibrational and electronic Raman scattering.
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Affiliation(s)
- Martin G Hell
- II. Physikalisches Institut , Universität zu Köln , Zülpicher Strasse 77 , 50937 Köln , Germany
| | - Niels Ehlen
- II. Physikalisches Institut , Universität zu Köln , Zülpicher Strasse 77 , 50937 Köln , Germany
| | - Boris V Senkovskiy
- II. Physikalisches Institut , Universität zu Köln , Zülpicher Strasse 77 , 50937 Köln , Germany
| | - Eddwi H Hasdeo
- Department of Physics , Tohoku University , Sendai 980-8578 , Japan
- Research Center for Physics , Indonesian Institute of Sciences , Kawasan Puspiptek Serpong , Tangerang Selatan 15314 , Indonesia
| | - Alexander Fedorov
- II. Physikalisches Institut , Universität zu Köln , Zülpicher Strasse 77 , 50937 Köln , Germany
| | - Daniela Dombrowski
- II. Physikalisches Institut , Universität zu Köln , Zülpicher Strasse 77 , 50937 Köln , Germany
- Institut für Materialphysik , Westfälische Wilhelms-Universität Münster , Wilhelm-Klemm-Str. 10 , 48149 Münster , Germany
| | - Carsten Busse
- II. Physikalisches Institut , Universität zu Köln , Zülpicher Strasse 77 , 50937 Köln , Germany
- Fakultät IV Physik , Universität Siegen , Walter-Flex-Str. 3 , 57072 Siegen , Germany
| | - Thomas Michely
- II. Physikalisches Institut , Universität zu Köln , Zülpicher Strasse 77 , 50937 Köln , Germany
| | - Giovanni di Santo
- Elettra Sincrotrone Trieste , Strada Statale 14 km 163.5 , 34149 Trieste , Italy
| | - Luca Petaccia
- Elettra Sincrotrone Trieste , Strada Statale 14 km 163.5 , 34149 Trieste , Italy
| | - Riichiro Saito
- Department of Physics , Tohoku University , Sendai 980-8578 , Japan
| | - Alexander Grüneis
- II. Physikalisches Institut , Universität zu Köln , Zülpicher Strasse 77 , 50937 Köln , Germany
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8
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Wu JB, Lin ML, Cong X, Liu HN, Tan PH. Raman spectroscopy of graphene-based materials and its applications in related devices. Chem Soc Rev 2018; 47:1822-1873. [PMID: 29368764 DOI: 10.1039/c6cs00915h] [Citation(s) in RCA: 512] [Impact Index Per Article: 85.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Graphene-based materials exhibit remarkable electronic, optical, and mechanical properties, which has resulted in both high scientific interest and huge potential for a variety of applications. Furthermore, the family of graphene-based materials is growing because of developments in preparation methods. Raman spectroscopy is a versatile tool to identify and characterize the chemical and physical properties of these materials, both at the laboratory and mass-production scale. This technique is so important that most of the papers published concerning these materials contain at least one Raman spectrum. Thus, here, we systematically review the developments in Raman spectroscopy of graphene-based materials from both fundamental research and practical (i.e., device applications) perspectives. We describe the essential Raman scattering processes of the entire first- and second-order modes in intrinsic graphene. Furthermore, the shear, layer-breathing, G and 2D modes of multilayer graphene with different stacking orders are discussed. Techniques to determine the number of graphene layers, to probe resonance Raman spectra of monolayer and multilayer graphenes and to obtain Raman images of graphene-based materials are also presented. The extensive capabilities of Raman spectroscopy for the investigation of the fundamental properties of graphene under external perturbations are described, which have also been extended to other graphene-based materials, such as graphene quantum dots, carbon dots, graphene oxide, nanoribbons, chemical vapor deposition-grown and SiC epitaxially grown graphene flakes, composites, and graphene-based van der Waals heterostructures. These fundamental properties have been used to probe the states, effects, and mechanisms of graphene materials present in the related heterostructures and devices. We hope that this review will be beneficial in all the aspects of graphene investigations, from basic research to material synthesis and device applications.
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Affiliation(s)
- Jiang-Bin Wu
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
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9
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Miranda HPC, Reichardt S, Froehlicher G, Molina-Sánchez A, Berciaud S, Wirtz L. Quantum Interference Effects in Resonant Raman Spectroscopy of Single- and Triple-Layer MoTe 2 from First-Principles. NANO LETTERS 2017; 17:2381-2388. [PMID: 28199122 DOI: 10.1021/acs.nanolett.6b05345] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We present a combined experimental and theoretical study of resonant Raman spectroscopy in single- and triple-layer MoTe2. Raman intensities are computed entirely from first-principles by calculating finite differences of the dielectric susceptibility. In our analysis, we investigate the role of quantum interference effects and the electron-phonon coupling. With this method, we explain the experimentally observed intensity inversion of the A1' vibrational modes in triple-layer MoTe2 with increasing laser photon energy. Finally, we show that a quantitative comparison with experimental data requires the proper inclusion of excitonic effects.
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Affiliation(s)
- Henrique P C Miranda
- Physics and Materials Science Research Unit, University of Luxembourg , 162a avenue de la Faïencerie, L-1511 Luxembourg, Luxembourg , EU
| | - Sven Reichardt
- Physics and Materials Science Research Unit, University of Luxembourg , 162a avenue de la Faïencerie, L-1511 Luxembourg, Luxembourg , EU
- JARA-FIT and 2nd Institute of Physics , Otto-Blumenthal-Straße, 52074 Aachen, Germany , EU
| | - Guillaume Froehlicher
- Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS , UMR 7504, F-67000 Strasbourg, France , EU
| | - Alejandro Molina-Sánchez
- Physics and Materials Science Research Unit, University of Luxembourg , 162a avenue de la Faïencerie, L-1511 Luxembourg, Luxembourg , EU
| | - Stéphane Berciaud
- Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg, CNRS , UMR 7504, F-67000 Strasbourg, France , EU
| | - Ludger Wirtz
- Physics and Materials Science Research Unit, University of Luxembourg , 162a avenue de la Faïencerie, L-1511 Luxembourg, Luxembourg , EU
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10
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Verzhbitskiy IA, Corato MD, Ruini A, Molinari E, Narita A, Hu Y, Schwab MG, Bruna M, Yoon D, Milana S, Feng X, Müllen K, Ferrari AC, Casiraghi C, Prezzi D. Raman Fingerprints of Atomically Precise Graphene Nanoribbons. NANO LETTERS 2016; 16:3442-7. [PMID: 26907096 PMCID: PMC4901367 DOI: 10.1021/acs.nanolett.5b04183] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 02/16/2016] [Indexed: 05/26/2023]
Abstract
Bottom-up approaches allow the production of ultranarrow and atomically precise graphene nanoribbons (GNRs) with electronic and optical properties controlled by the specific atomic structure. Combining Raman spectroscopy and ab initio simulations, we show that GNR width, edge geometry, and functional groups all influence their Raman spectra. The low-energy spectral region below 1000 cm(-1) is particularly sensitive to edge morphology and functionalization, while the D peak dispersion can be used to uniquely fingerprint the presence of GNRs and differentiates them from other sp(2) carbon nanostructures.
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Affiliation(s)
| | - Marzio De Corato
- Department of Physics, Mathematics, and Informatics, University of Modena and Reggio Emilia, 41121 Modena, Italy
- Nanoscience Institute of CNR, S3 Center, 41125 Modena, Italy
| | - Alice Ruini
- Department of Physics, Mathematics, and Informatics, University of Modena and Reggio Emilia, 41121 Modena, Italy
- Nanoscience Institute of CNR, S3 Center, 41125 Modena, Italy
| | - Elisa Molinari
- Department of Physics, Mathematics, and Informatics, University of Modena and Reggio Emilia, 41121 Modena, Italy
- Nanoscience Institute of CNR, S3 Center, 41125 Modena, Italy
| | - Akimitsu Narita
- Max Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Yunbin Hu
- Max Planck Institute for Polymer Research, 55128 Mainz, Germany
| | | | - Matteo Bruna
- Cambridge Graphene Centre, University of Cambridge, Cambridge, CB3 OFA, United Kingdom
| | - Duhee Yoon
- Cambridge Graphene Centre, University of Cambridge, Cambridge, CB3 OFA, United Kingdom
| | - Silvia Milana
- Cambridge Graphene Centre, University of Cambridge, Cambridge, CB3 OFA, United Kingdom
| | - Xinliang Feng
- Center
for Advancing Electronics Dresden (cfaed) and Department of Chemistry
and Food Chemistry, Technische Universitaet
Dresden, 01069 Dresden, Germany
| | - Klaus Müllen
- Max Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Andrea C. Ferrari
- Cambridge Graphene Centre, University of Cambridge, Cambridge, CB3 OFA, United Kingdom
| | - Cinzia Casiraghi
- Physics Department, Free University of Berlin, 14195 Berlin, Germany
- School of Chemistry, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Deborah Prezzi
- Nanoscience Institute of CNR, S3 Center, 41125 Modena, Italy
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11
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Beams R, Gustavo Cançado L, Novotny L. Raman characterization of defects and dopants in graphene. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:083002. [PMID: 25634863 DOI: 10.1088/0953-8984/27/8/083002] [Citation(s) in RCA: 141] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
In this article we review Raman studies of defects and dopants in graphene as well as the importance of both for device applications. First a brief overview of Raman spectroscopy of graphene is presented. In the following section we discuss the Raman characterization of three defect types: point defects, edges, and grain boundaries. The next section reviews the dependence of the Raman spectrum on dopants and highlights several common doping techniques. In the final section, several device applications are discussed which exploit doping and defects in graphene. Generally defects degrade the figures of merit for devices, such as carrier mobility and conductivity, whereas doping provides a means to tune the carrier concentration in graphene thereby enabling the engineering of novel material systems. Accurately measuring both the defect density and doping is critical and Raman spectroscopy provides a powerful tool to accomplish this task.
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Affiliation(s)
- Ryan Beams
- Institute of Optics, University of Rochester, Rochester, NY 14627, USA
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12
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Frank O, Dresselhaus MS, Kalbac M. Raman spectroscopy and in situ Raman spectroelectrochemistry of isotopically engineered graphene systems. Acc Chem Res 2015; 48:111-8. [PMID: 25569178 DOI: 10.1021/ar500384p] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
CONSPECTUS: The special properties of graphene offer immense opportunities for applications to many scientific fields, as well as societal needs, beyond our present imagination. One of the important features of graphene is the relatively simple tunability of its electronic structure, an asset that extends the usability of graphene even further beyond present experience. A direct injection of charge carriers into the conduction or valence bands, that is, doping, represents a viable way of shifting the Fermi level. In particular, electrochemical doping should be the method of choice, when higher doping levels are desired and when a firm control of experimental conditions is needed. In this Account, we focus on the electrochemistry of graphene in combination with in situ Raman spectroscopy, that is, in situ Raman spectroelectrochemistry. Such a combination of methods is indeed very powerful, since Raman spectroscopy not only can readily monitor the changes in the doping level but also can give information on eventual stress or disorder in the material. However, when Raman spectroscopy is employed, one of its main strengths lies in the utilization of isotope engineering during the chemical vapor deposition (CVD) growth of the graphene samples. The in situ Raman spectroelectrochemical study of multilayered systems with smartly designed isotope compositions in individual layers can provide a plethora of knowledge about the mutual interactions (i) between the graphene layers themselves, (ii) between graphene layers and their directly adjacent environment (e.g., substrate or electrolyte), and (iii) between graphene layers and their extended environment, which is separated from the layer by a certain number of additional graphene layers. In this Account, we show a few examples of such studies, from monolayer to two-layer and three-layer specimens and considering both turbostratic and AB interlayer ordering. Furthermore, the concept and the method can be extended further beyond the three-layer systems, for example, to heterostructures containing other 2-D materials beyond graphene. Despite a great deal of important results being unraveled so far through the in situ spectroelectrochemistry of graphene based systems, many intriguing challenges still lie immediately ahead. For example, apart from the aforementioned 2-D heterostructures, a substantial effort should be put into a more detailed exploration of misoriented (twisted) bilayer or trilayer graphenes. Marching from the oriented, AB-stacked to AA-stacked, bilayers, every single angular increment of the twist between the layers creates a new system in terms of its electronic properties. Mapping those properties and interlayer interactions dependent on the twist angle represents a sizable task, yet the reward might be the path toward the realization of various types of advanced devices. And last but not least, understanding the electrochemistry of graphene paves the way toward a controlled and targeted functionalization of graphene through redox reactions, especially when equipped with the possibility of an instantaneous monitoring of the thus introduced changes to the electronic structure of the system.
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Affiliation(s)
- Otakar Frank
- J. Heyrovský Institute of Physical Chemistry of the Academy of Sciences of the Czech Republic, v.v.i., Dolejškova 3, CZ-18223 Prague 8, Czech Republic
| | - Mildred S. Dresselhaus
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Martin Kalbac
- J. Heyrovský Institute of Physical Chemistry of the Academy of Sciences of the Czech Republic, v.v.i., Dolejškova 3, CZ-18223 Prague 8, Czech Republic
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Yeh CH, Lin YC, Chen YC, Lu CC, Liu Z, Suenaga K, Chiu PW. Gating electron-hole asymmetry in twisted bilayer graphene. ACS NANO 2014; 8:6962-6969. [PMID: 24999754 DOI: 10.1021/nn501775h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Electron-hole symmetry is one of the unique properties of graphene that is generally absent in most semiconductors because of the different conduction and valence band structures. Here we report on the manipulation of electron-hole symmetry in the low-energy band structure of twisted bilayer graphene, where symmetric saddle points form in the conduction and valence bands as a result of interlayer coupling. By applying a gate voltage to a twisted bilayer with a critical rotation angle, enhanced electron resonance between the two saddle points can be turned on or off, depending on the electron-hole symmetry near the saddle points. The appearance of a 2D(+) peak, a gate-tunable Raman feature found near the critical angle, indicates a reduction of Fermi velocity in the vicinity of the saddle point to/from which electrons are inelastically scattered by phonons in the round trip of the double-resonance process.
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Affiliation(s)
- Chao-Hui Yeh
- Department of Electrical Engineering, National Tsing Hua University , Hsinchu 30013, Taiwan
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Bruna M, Ott AK, Ijäs M, Yoon D, Sassi U, Ferrari AC. Doping dependence of the Raman spectrum of defected graphene. ACS NANO 2014; 8:7432-41. [PMID: 24960180 DOI: 10.1021/nn502676g] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We investigate the evolution of the Raman spectrum of defected graphene as a function of doping. Polymer electrolyte gating allows us to move the Fermi level up to 0.7 eV, as directly monitored by in situ Hall-effect measurements. For a given number of defects, we find that the intensities of the D and D' peaks decrease with increasing doping. We assign this to an increased total scattering rate of the photoexcited electrons and holes, due to the doping-dependent strength of electron-electron scattering. We present a general relation between D peak intensity and defects valid for any doping level.
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Affiliation(s)
- Matteo Bruna
- Cambridge Graphene Centre, University of Cambridge , Cambridge CB3 0FA, U.K
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15
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Kominkova Z, Kalbac M. Extreme electrochemical doping of a graphene–polyelectrolyte heterostructure. RSC Adv 2014. [DOI: 10.1039/c3ra44780d] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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16
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Kim Y, Poumirol JM, Lombardo A, Kalugin NG, Georgiou T, Kim YJ, Novoselov KS, Ferrari AC, Kono J, Kashuba O, Fal'ko VI, Smirnov D. Measurement of filling-factor-dependent magnetophonon resonances in graphene using Raman spectroscopy. PHYSICAL REVIEW LETTERS 2013; 110:227402. [PMID: 23767746 DOI: 10.1103/physrevlett.110.227402] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Indexed: 06/02/2023]
Abstract
We perform polarization-resolved Raman spectroscopy on graphene in magnetic fields up to 45 T. This reveals a filling-factor-dependent, multicomponent anticrossing structure of the Raman G peak, resulting from magnetophonon resonances between magnetoexcitons and E(2g) phonons. This is explained with a model of Raman scattering taking into account the effects of spatially inhomogeneous carrier densities and strain. Random fluctuations of strain-induced pseudomagnetic fields lead to increased scattering intensity inside the anticrossing gap, consistent with the experiments.
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Affiliation(s)
- Y Kim
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310, USA
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17
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Sahni D, Jea A, Mata JA, Marcano DC, Sivaganesan A, Berlin JM, Tatsui CE, Sun Z, Luerssen TG, Meng S, Kent TA, Tour JM. Biocompatibility of pristine graphene for neuronal interface. J Neurosurg Pediatr 2013; 11:575-83. [PMID: 23473006 DOI: 10.3171/2013.1.peds12374] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Graphene possesses unique electrical, physical, and chemical properties that may offer significant potential as a bioscaffold for neuronal regeneration after spinal cord injury. The purpose of this investigation was to establish the in vitro biocompatibility of pristine graphene for interface with primary rat cortical neurons. METHODS Graphene films were prepared by chemical vapor deposition on a copper foil catalytic substrate and subsequent apposition on bare Permanox plastic polymer dishes. Rat neuronal cell culture was grown on graphene-coated surfaces, and cell growth and attachment were compared with those on uncoated and poly-d-lysine (PDL)-coated controls; the latter surface is highly favorable for neuronal attachment and growth. Live/dead cell analysis was conducted with flow cytometry using ethidium homodimer-1 and calcein AM dyes. Lactate dehydrogenase (LDH) levels-indicative of cytotoxicity-were measured as markers of cell death. Phase contrast microscopy of active cell culture was conducted to assess neuronal attachment and morphology. RESULTS Statistically significant differences in the percentage of live or dead neurons were noted between graphene and PDL surfaces, as well as between the PDL-coated and bare surfaces, but there was little difference in cell viability between graphene-coated and bare surfaces. There were significantly lower LDH levels in the graphene-coated samples compared with the uncoated ones, indicating that graphene was not more cytotoxic than the bare control surface. According to phase contrast microscopy, neurons attached to the graphene-coated surface and were able to elaborate long, neuritic processes suggestive of normal neuronal metabolism and morphology. CONCLUSIONS Further use of graphene as a bioscaffold will require surface modification that enhances hydrophilicity to increase cellular attachment and growth. Graphene is a nanomaterial that is biocompatible with neurons and may have significant biomedical applications.
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Affiliation(s)
- Deshdeepak Sahni
- Department of Neurosurgery, Baylor College of Medicine, Houston, TX, USA
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18
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Ferrari AC, Basko DM. Raman spectroscopy as a versatile tool for studying the properties of graphene. NATURE NANOTECHNOLOGY 2013; 8:235-46. [PMID: 23552117 DOI: 10.1038/nnano.2013.46] [Citation(s) in RCA: 2215] [Impact Index Per Article: 201.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Accepted: 03/01/2013] [Indexed: 05/19/2023]
Abstract
Raman spectroscopy is an integral part of graphene research. It is used to determine the number and orientation of layers, the quality and types of edge, and the effects of perturbations, such as electric and magnetic fields, strain, doping, disorder and functional groups. This, in turn, provides insight into all sp(2)-bonded carbon allotropes, because graphene is their fundamental building block. Here we review the state of the art, future directions and open questions in Raman spectroscopy of graphene. We describe essential physical processes whose importance has only recently been recognized, such as the various types of resonance at play, and the role of quantum interference. We update all basic concepts and notations, and propose a terminology that is able to describe any result in literature. We finally highlight the potential of Raman spectroscopy for layered materials other than graphene.
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Affiliation(s)
- Andrea C Ferrari
- Cambridge Graphene Centre, Cambridge University, 9 JJ Thomson Avenue, Cambridge CB3 OFA, UK.
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Dimiev AM, Bachilo SM, Saito R, Tour JM. Reversible formation of ammonium persulfate/sulfuric acid graphite intercalation compounds and their peculiar Raman spectra. ACS NANO 2012; 6:7842-9. [PMID: 22880798 DOI: 10.1021/nn3020147] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Graphite intercalation compounds (GICs) can be considered stacks of individual doped graphene layers. Here we demonstrate a reversible formation of sulfuric acid-based GICs using ammonium persulfate as the chemical oxidizing agent. No covalent chemical oxidation leading to the formation of graphite oxide occurs, which inevitably happens when other compounds such as potassium permanganate are used to charge carbon layers. The resulting acid/persulfate-induced stage-1 and stage-2 GICs are characterized by suppression of the 2D band in the Raman spectra and by unusually strong enhancement of the G band. The G band is selectively enhanced at different doping levels with different excitations. These observations are in line with recent reports for chemically doped and gate-modulated graphene and support newly proposed theories of Raman processes. At the same time GICs have some advantageous differences over graphene, which are demonstrated in this report. Our experimental observations, along with earlier reported data, suggest that at high doping levels the G band cannot be used as the reference peak for normalizing Raman spectra, which is a commonly used practice today. A Fermi energy shift of 1.20-1.25 eV and ∼1.0 eV was estimated for the stage-1 and stage-2 GICs, respectively, from the Raman and optical spectroscopy data.
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Affiliation(s)
- Ayrat M Dimiev
- Department of Chemistry, the Smalley Institute for Nanoscale Science and Technology, Rice University, MS-222, 6100 Main Street, Houston, Texas 77005, United States
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Havener RW, Zhuang H, Brown L, Hennig RG, Park J. Angle-resolved Raman imaging of interlayer rotations and interactions in twisted bilayer graphene. NANO LETTERS 2012; 12:3162-7. [PMID: 22612855 DOI: 10.1021/nl301137k] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Few-layer graphene is a prototypical layered material, whose properties are determined by the relative orientations and interactions between layers. Exciting electrical and optical phenomena have been observed for the special case of Bernal-stacked few-layer graphene, but structure-property correlations in graphene which deviates from this structure are not well understood. Here, we combine two direct imaging techniques, dark-field transmission electron microscopy (DF-TEM) and widefield Raman imaging, to establish a robust, one-to-one correlation between twist angle and Raman intensity in twisted bilayer graphene (tBLG). The Raman G band intensity is strongly enhanced due to a previously unreported singularity in the joint density of states of tBLG, whose energy is exclusively a function of twist angle and whose optical transition strength is governed by interlayer interactions, enabling direct optical imaging of these parameters. Furthermore, our findings suggest future potential for novel optical and optoelectronic tBLG devices with angle-dependent, tunable characteristics.
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Affiliation(s)
- Robin W Havener
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
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Cançado LG, Jorio A, Ferreira EHM, Stavale F, Achete CA, Capaz RB, Moutinho MVO, Lombardo A, Kulmala TS, Ferrari AC. Quantifying defects in graphene via Raman spectroscopy at different excitation energies. NANO LETTERS 2011; 11:3190-6. [PMID: 21696186 DOI: 10.1021/nl201432g] [Citation(s) in RCA: 1108] [Impact Index Per Article: 85.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We present a Raman study of Ar(+)-bombarded graphene samples with increasing ion doses. This allows us to have a controlled, increasing, amount of defects. We find that the ratio between the D and G peak intensities, for a given defect density, strongly depends on the laser excitation energy. We quantify this effect and present a simple equation for the determination of the point defect density in graphene via Raman spectroscopy for any visible excitation energy. We note that, for all excitations, the D to G intensity ratio reaches a maximum for an interdefect distance ∼3 nm. Thus, a given ratio could correspond to two different defect densities, above or below the maximum. The analysis of the G peak width and its dispersion with excitation energy solves this ambiguity.
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Affiliation(s)
- L G Cançado
- Departamento de Física, Universidade Federal de Minas Gerais, 30123-970, Belo Horizonte, Brazil.
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Kalbac M, Farhat H, Kong J, Janda P, Kavan L, Dresselhaus MS. Raman spectroscopy and in situ Raman spectroelectrochemistry of bilayer ¹²C/¹³C graphene. NANO LETTERS 2011; 11:1957-1963. [PMID: 21506590 DOI: 10.1021/nl2001956] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Bilayer graphene was prepared by the subsequent deposition of a (13)C single-layer graphene and a (12)C single-layer graphene on top of a SiO(2)/Si substrate. The bilayer graphene thus prepared was studied using Raman spectroscopy and in situ Raman spectroelectrochemistry. The Raman frequencies of the (13)C graphene bands are significantly shifted with respect to those of (12)C graphene, which allows us to investigate the single layer components of bilayer graphene individually. It is shown that the bottom layer of the bilayer graphene is significantly doped from the substrate, while the top layer does not exhibit a signature of the doping from the environment. The electrochemical doping has the same effect on the charge carrier concentration at the top and the bottom layer despite the top layer being the only layer in contact with the electrolyte. This is here demonstrated by essentially the same frequency shifts of the G and G' bands as a function of the electrode potential for both the top and bottom layers. Nevertheless, analysis of the intensity of the Raman modes showed an anomalous bleaching of the Raman intensity of the G mode with increasing electrode potential, which was not observed previously in one-layer graphene.
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Affiliation(s)
- Martin Kalbac
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v.v.i., Dolejškova 3, CZ-18223 Prague 8, Czech Republic.
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Chen CF, Park CH, Boudouris BW, Horng J, Geng B, Girit C, Zettl A, Crommie MF, Segalman RA, Louie SG, Wang F. Controlling inelastic light scattering quantum pathways in graphene. Nature 2011; 471:617-20. [DOI: 10.1038/nature09866] [Citation(s) in RCA: 436] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Accepted: 01/18/2011] [Indexed: 12/23/2022]
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Kalbac M, Reina-Cecco A, Farhat H, Kong J, Kavan L, Dresselhaus MS. The influence of strong electron and hole doping on the Raman intensity of chemical vapor-deposition graphene. ACS NANO 2010; 4:6055-6063. [PMID: 20931995 DOI: 10.1021/nn1010914] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Electrochemical charging has been applied to study the influence of doping on the intensity of the various Raman features observed in chemical vapor-deposition-grown graphene. Three different laser excitation energies have been used to probe the influence of the excitation energy on the behavior of both the G and G' modes regarding their dependence on doping. The intensities of both the G and G' modes exhibit a significant but different dependence on doping. While the intensity of the G' band monotonically decreases with increasing magnitude of the electrode potential (positive or negative), for the G band a more complex behavior has been found. The striking feature is an increase of the Raman intensity of the G mode at a high value of the positive electrode potential. Furthermore, the observed increase of the Raman intensity of the G mode is found to be a function of laser excitation energy.
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Affiliation(s)
- Martin Kalbac
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v.v.i., Dolejškova 3, CZ-18223 Prague 8, Czech Republic.
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