1
|
Winkler R, Ciria M, Ahmad M, Plank H, Marcuello C. A Review of the Current State of Magnetic Force Microscopy to Unravel the Magnetic Properties of Nanomaterials Applied in Biological Systems and Future Directions for Quantum Technologies. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2585. [PMID: 37764614 PMCID: PMC10536909 DOI: 10.3390/nano13182585] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 09/13/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023]
Abstract
Magnetism plays a pivotal role in many biological systems. However, the intensity of the magnetic forces exerted between magnetic bodies is usually low, which demands the development of ultra-sensitivity tools for proper sensing. In this framework, magnetic force microscopy (MFM) offers excellent lateral resolution and the possibility of conducting single-molecule studies like other single-probe microscopy (SPM) techniques. This comprehensive review attempts to describe the paramount importance of magnetic forces for biological applications by highlighting MFM's main advantages but also intrinsic limitations. While the working principles are described in depth, the article also focuses on novel micro- and nanofabrication procedures for MFM tips, which enhance the magnetic response signal of tested biomaterials compared to commercial nanoprobes. This work also depicts some relevant examples where MFM can quantitatively assess the magnetic performance of nanomaterials involved in biological systems, including magnetotactic bacteria, cryptochrome flavoproteins, and magnetic nanoparticles that can interact with animal tissues. Additionally, the most promising perspectives in this field are highlighted to make the reader aware of upcoming challenges when aiming toward quantum technologies.
Collapse
Affiliation(s)
- Robert Winkler
- Christian Doppler Laboratory—DEFINE, Graz University of Technology, 8010 Graz, Austria; (R.W.); (H.P.)
| | - Miguel Ciria
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain;
- Departamento de Física de la Materia Condensada, Universidad de Zaragoza, 50009 Zaragoza, Spain
| | - Margaret Ahmad
- Photobiology Research Group, IBPS, UMR8256 CNRS, Sorbonne Université, 75005 Paris, France;
| | - Harald Plank
- Christian Doppler Laboratory—DEFINE, Graz University of Technology, 8010 Graz, Austria; (R.W.); (H.P.)
- Graz Centre for Electron Microscopy, 8010 Graz, Austria
- Institute of Electron Microscopy, Graz University of Technology, 8010 Graz, Austria
| | - Carlos Marcuello
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain;
- Laboratorio de Microscopias Avanzadas (LMA), Universidad de Zaragoza, 50018 Zaragoza, Spain
| |
Collapse
|
2
|
Corte-León H, Neu V, Manzin A, Barton C, Tang Y, Gerken M, Klapetek P, Schumacher HW, Kazakova O. Comparison and Validation of Different Magnetic Force Microscopy Calibration Schemes. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e1906144. [PMID: 32037728 DOI: 10.1002/smll.201906144] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 01/01/2020] [Indexed: 06/10/2023]
Abstract
The future of consumer electronics depends on the capability to reliably fabricate nanostructures with given physical properties. Therefore, techniques to characterize materials and devices with nanoscale resolution are crucial. Among these is magnetic force microscopy (MFM), which transduces the magnetic force between the sample and a magnetic oscillating probe into a phase shift, enabling the locally resolved study of magnetic field patterns down to 10 nm. Here, the progress done toward making quantitative MFM a common tool in nanocharacterization laboratories is shown. The reliability and ease of use of the calibration method based on a magnetic reference sample, with a calculable stray field, and a deconvolution algorithm is demonstrated. This is achieved by comparing two calibration approaches combined with numerical modeling as a quantitative link: measuring the probe's effect on the voltage signal when scanning above a nanosized graphene Hall sensor, and recording the MFM phase shift signal when the probe scans across magnetic fields produced by metallic microcoils. Furthermore, in the case of the deconvolution algorithm, it is shown how it can be applied using the open-source software package Gwyddion. The estimated magnetic dipole approximation for the most common probes currently in the market is also reported.
Collapse
Affiliation(s)
- Héctor Corte-León
- National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, UK
| | - Volker Neu
- Leibniz IFW Dresden, Helmholtzstr. 20, 01069, Dresden, Germany
| | | | - Craig Barton
- National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, UK
| | - Yuanjun Tang
- Leibniz IFW Dresden, Helmholtzstr. 20, 01069, Dresden, Germany
| | - Manuela Gerken
- Physikalisch-Technische Bundesanstalt, Braunschweig, D-38116, Germany
| | - Petr Klapetek
- Department of Nanometrology, Czech Metrology Institute Okružní 31, 638 00, Brno, Czech Republic
| | | | - Olga Kazakova
- National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, UK
| |
Collapse
|
3
|
Lenz K, Narkowicz R, Wagner K, Reiche CF, Körner J, Schneider T, Kákay A, Schultheiss H, Weissker U, Wolf D, Suter D, Büchner B, Fassbender J, Mühl T, Lindner J. Magnetization Dynamics of an Individual Single-Crystalline Fe-Filled Carbon Nanotube. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2019; 15:e1904315. [PMID: 31709700 DOI: 10.1002/smll.201904315] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 09/20/2019] [Indexed: 06/10/2023]
Abstract
The magnetization dynamics of individual Fe-filled multiwall carbon-nanotubes (FeCNT), grown by chemical vapor deposition, are investigated by microresonator ferromagnetic resonance (FMR) and Brillouin light scattering (BLS) microscopy and corroborated by micromagnetic simulations. Currently, only static magnetometry measurements are available. They suggest that the FeCNTs consist of a single-crystalline Fe nanowire throughout the length. The number and structure of the FMR lines and the abrupt decay of the spin-wave transport seen in BLS indicate, however, that the Fe filling is not a single straight piece along the length. Therefore, a stepwise cutting procedure is applied in order to investigate the evolution of the ferromagnetic resonance lines as a function of the nanowire length. The results show that the FeCNT is indeed not homogeneous along the full length but is built from 300 to 400 nm long single-crystalline segments. These segments consist of magnetically high quality Fe nanowires with almost the bulk values of Fe and with a similar small damping in relation to thin films, promoting FeCNTs as appealing candidates for spin-wave transport in magnonic applications.
Collapse
Affiliation(s)
- Kilian Lenz
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, Bautzner Landstr. 400, 01328, Dresden, Germany
| | - Ryszard Narkowicz
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, Bautzner Landstr. 400, 01328, Dresden, Germany
| | - Kai Wagner
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, Bautzner Landstr. 400, 01328, Dresden, Germany
| | - Christopher F Reiche
- Leibniz Institute for Solid State and Materials Research, IFW Dresden, Helmholtzstr. 20, 01069, Dresden, Germany
| | - Julia Körner
- Leibniz Institute for Solid State and Materials Research, IFW Dresden, Helmholtzstr. 20, 01069, Dresden, Germany
| | - Tobias Schneider
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, Bautzner Landstr. 400, 01328, Dresden, Germany
- Technische Universität Chemnitz, Institute of Physics, Reichenhainer Str. 70, 09107, Chemnitz, Germany
| | - Attila Kákay
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, Bautzner Landstr. 400, 01328, Dresden, Germany
| | - Helmut Schultheiss
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, Bautzner Landstr. 400, 01328, Dresden, Germany
- Institute for Physics of Solids, Technische Universität Dresden, Zellescher Weg 16, 01069, Dresden, Germany
| | - Uhland Weissker
- Leibniz Institute for Solid State and Materials Research, IFW Dresden, Helmholtzstr. 20, 01069, Dresden, Germany
- Transfer Office, Technische Universität Dresden, Helmholtzstr. 9, 01069, Dresden, Germany
| | - Daniel Wolf
- Leibniz Institute for Solid State and Materials Research, IFW Dresden, Helmholtzstr. 20, 01069, Dresden, Germany
| | - Dieter Suter
- Department of Physics, Technical University of Dortmund, Otto-Hahn-Straße 4a, 44227, Dortmund, Germany
| | - Bernd Büchner
- Leibniz Institute for Solid State and Materials Research, IFW Dresden, Helmholtzstr. 20, 01069, Dresden, Germany
- Institute for Physics of Solids, Technische Universität Dresden, Zellescher Weg 16, 01069, Dresden, Germany
- Center for Transport and Devices of Emergent Materials, Technische Universität Dresden, 01062, Dresden, Germany
| | - Jürgen Fassbender
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, Bautzner Landstr. 400, 01328, Dresden, Germany
- Institute for Physics of Solids, Technische Universität Dresden, Zellescher Weg 16, 01069, Dresden, Germany
| | - Thomas Mühl
- Leibniz Institute for Solid State and Materials Research, IFW Dresden, Helmholtzstr. 20, 01069, Dresden, Germany
- Center for Transport and Devices of Emergent Materials, Technische Universität Dresden, 01062, Dresden, Germany
| | - Jürgen Lindner
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, Bautzner Landstr. 400, 01328, Dresden, Germany
| |
Collapse
|
4
|
Corte-León H, Rodríguez LA, Pancaldi M, Gatel C, Cox D, Snoeck E, Antonov V, Vavassori P, Kazakova O. Magnetic imaging using geometrically constrained nano-domain walls. NANOSCALE 2019; 11:4478-4488. [PMID: 30805582 DOI: 10.1039/c8nr07729k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Magnetic nanostructures, as part of hybrid CMOS technology, have the potential to overcome silicon's scaling limit. However, a major problem is how to characterize their magnetization without disturbing it. Magnetic force microscopy (MFM) offers a convenient way of studying magnetization, but spatial resolution and sensitivity are usually boosted at the cost of increasing probe-sample interaction. By using a single magnetic domain wall (DW), confined in a V-shape nanostructure fabricated at the probe apex, it is demonstrated here that the spatial resolution and the magnetic sensitivity can be decoupled and both enhanced. Indeed, owing to the nanostructure's strong shape anisotropy, DW-probes have 2 high and 2 low magnetic moment states with opposite polarities, characterised by a geometrically constrained pinned DW, and curled magnetization, respectively. Electron holography studies, supported by numerical simulations, and in situ MFM show that the DW-probe state can be controlled, and thus used as a switchable tool with a low/high stray field intensity.
Collapse
|
5
|
Wren T, Puttock R, Gribkov B, Vdovichev S, Kazakova O. Switchable bi-stable multilayer magnetic probes for imaging of soft magnetic structures. Ultramicroscopy 2017; 179:41-46. [PMID: 28391037 DOI: 10.1016/j.ultramic.2017.03.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 03/24/2017] [Accepted: 03/27/2017] [Indexed: 10/19/2022]
Abstract
We present the use of custom-made multilayer (ML) magnetic probes in magnetic force microscopy (MFM) for imaging soft magnetic structures, i.e. nickel submicron disks of different dimensions. One of the main advantages of a custom-made ML probe is that it can be controllably switched between standard (parallel) and low moment (antiparallel) states. We demonstrate that the predicted vortex and stripe domain states in the disks are observed when using the ML probes both in the antiparallel and parallel states. However, while the phase contrast is significantly larger in the parallel state, the images are dominated by strong sample - probe interactions that obscure the image. By comparison of the stripe domain width observed by MFM with the ML probe and those expected from the Kittel model, we show that the resolution of the probe in the AP and P states is ∼30-40nm, i.e. of the order of the probe geometrical apex and thus approaching the limit of spatial resolution. The ML probes are further compared to the commercial standard and low moment ones, showing that the quality of images obtained with the ML probe is superior to both commercial probes.
Collapse
Affiliation(s)
- Tom Wren
- National Physical Laboratory, Teddington, TW11 0LW, UK; Royal Holloway University London, Egham, TW20 0EX, UK
| | - Robb Puttock
- National Physical Laboratory, Teddington, TW11 0LW, UK; Royal Holloway University London, Egham, TW20 0EX, UK
| | - Boris Gribkov
- National Physical Laboratory, Teddington, TW11 0LW, UK; Institute for Physics of Microstructures RAS, Nizhny Novgorod 603950, Russia
| | - Sergey Vdovichev
- Institute for Physics of Microstructures RAS, Nizhny Novgorod 603950, Russia
| | - Olga Kazakova
- National Physical Laboratory, Teddington, TW11 0LW, UK.
| |
Collapse
|
6
|
Guo J, Liu J, Lan M, Hu Y, Wang S, Wen J, He Y, Gao F, Zhang X, Zhang S, Xiang G, Willis MAC, Boi FS. Observation of large coercivities in radial carbon nanotube structures filled with Fe3C and FeCo single-crystals by viscous boundary layer pyrolysis of ferrocene and cobaltocene. RSC Adv 2017. [DOI: 10.1039/c6ra27888d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Viscous boundary layer chemical vapor synthesis is a novel technique that uses the viscous boundary layer between a metallocene/Ar vapor and a rough surface to induce the formation of radial CNT structures highly filled with ferromagnetic materials.
Collapse
|
7
|
Körner J, Reiche CF, Gemming T, Büchner B, Gerlach G, Mühl T. Signal enhancement in cantilever magnetometry based on a co-resonantly coupled sensor. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2016; 7:1033-43. [PMID: 27547621 PMCID: PMC4979692 DOI: 10.3762/bjnano.7.96] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 07/06/2016] [Indexed: 06/06/2023]
Abstract
Cantilever magnetometry is a measurement technique used to study magnetic nanoparticles. With decreasing sample size, the signal strength is significantly reduced, requiring advances of the technique. Ultrathin and slender cantilevers can address this challenge but lead to increased complexity of detection. We present an approach based on the co-resonant coupling of a micro- and a nanometer-sized cantilever. Via matching of the resonance frequencies of the two subsystems we induce a strong interplay between the oscillations of the two cantilevers, allowing for a detection of interactions between the sensitive nanocantilever and external influences in the amplitude response curve of the microcantilever. In our magnetometry experiment we used an iron-filled carbon nanotube acting simultaneously as nanocantilever and magnetic sample. Measurements revealed an enhancement of the commonly used frequency shift signal by five orders of magnitude compared to conventional cantilever magnetometry experiments with similar nanomagnets. With this experiment we do not only demonstrate the functionality of our sensor design but also its potential for very sensitive magnetometry measurements while maintaining a facile oscillation detection with a conventional microcantilever setup.
Collapse
Affiliation(s)
- Julia Körner
- Leibniz Institute for Solid State and Materials Research IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany
| | - Christopher F Reiche
- Leibniz Institute for Solid State and Materials Research IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany
| | - Thomas Gemming
- Leibniz Institute for Solid State and Materials Research IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany
| | - Bernd Büchner
- Leibniz Institute for Solid State and Materials Research IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany
- Institut für Festkörperphysik, Technische Universität Dresden, 01062 Dresden, Germany
| | - Gerald Gerlach
- Institut für Festkörperelektronik, Technische Universität Dresden, 01062 Dresden, Germany
| | - Thomas Mühl
- Leibniz Institute for Solid State and Materials Research IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany
| |
Collapse
|
8
|
Kumari R, Krishnia L, Kumar V, Singh S, Singh HK, Kotnala RK, Juluri RR, Bhatta UM, Satyam PV, Yadav BS, Naqvi Z, Tyagi PK. Fe3C-filled carbon nanotubes: permanent cylindrical nanomagnets possessing exotic magnetic properties. NANOSCALE 2016; 8:4299-4310. [PMID: 26839090 DOI: 10.1039/c5nr09188h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The present study aims to deduce the confinement effect on the magnetic properties of iron carbide (Fe3C) nanorods filled inside carbon nanotubes (CNTs), and to document any structural phase transitions that can be induced by compressive/tensile stress generated within the nanorod. Enhancement in the magnetic properties of the nanorods is attributed to tensile stress as well as to compression, present in the radial direction and along the nanotube axis, respectively. Finally, the growth of permanent cylindrical nanomagnets has been optimized by applying a field gradient. Besides presenting the growth model of in situ filling, we have also proposed the mechanism of magnetization of the nanotubes. Magnetization along the tube axis has been probed by confirming the pole formation. Fe3C has been selected because of its ease of formation, low TC and incompressibility.
Collapse
Affiliation(s)
- Reetu Kumari
- Department of Applied Physics, Delhi Technological University, Delhi, India.
| | - Lucky Krishnia
- Department of Applied Physics, Delhi Technological University, Delhi, India.
| | - Vinay Kumar
- Department of Applied Physics, Delhi Technological University, Delhi, India.
| | - Sandeep Singh
- Department of Applied Physics, Delhi Technological University, Delhi, India. and National Physical Laboratory, Delhi, India
| | - H K Singh
- National Physical Laboratory, Delhi, India
| | | | - R R Juluri
- Institute of Physics, Sachivalaya Marg, Bhubaneswar 751005, India
| | - U M Bhatta
- Centre for Emerging Technologies, Jain University, Jakkasandra, Kanakapura Taluk, Ramanagaram Dist, Karnataka 562 112, India
| | - P V Satyam
- Institute of Physics, Sachivalaya Marg, Bhubaneswar 751005, India
| | - Brajesh S Yadav
- Solid State Physics Laboratory, Lucknow Road, Timarpur, Delhi 110054, India
| | - Zainab Naqvi
- Department of Applied Physics, Delhi Technological University, Delhi, India.
| | - Pawan K Tyagi
- Department of Applied Physics, Delhi Technological University, Delhi, India.
| |
Collapse
|
9
|
Boi FS, Wilson RM, Mountjoy G, Ibrar M, Baxendale M. Boundary layer chemical vapour synthesis of self-organised ferromagnetically filled radial-carbon-nanotube structures. Faraday Discuss 2014; 173:67-77. [PMID: 25466445 DOI: 10.1039/c4fd00071d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Boundary layer chemical vapour synthesis is a new technique that exploits random fluctuations in the viscous boundary layer between a laminar flow of pyrolysed metallocene vapour and a rough substrate to yield ferromagnetically filled radial-carbon-nanotube structures departing from a core agglomeration of spherical nanocrystals individually encapsulated by graphitic shells. The fluctuations create the thermodynamic conditions for the formation of the central agglomeration in the vapour which subsequently defines the spherically symmetric diffusion gradient that initiates the radial growth. The radial growth is driven by the supply of vapour feedstock by local diffusion gradients created by endothermic graphitic-carbon formation at the vapour-facing tips of the individual nanotubes and is halted by contact with the isothermal substrate. The radial structures are the dominant product and the reaction conditions are self-sustaining. Ferrocene pyrolysis yields three common components in the nanowire encapsulated by multiwall carbon nanotubes, Fe3C, α-Fe, and γ-Fe. Magnetic tuning in this system can be achieved through the magnetocrystalline and shape anisotropies of the encapsulated nanowire. Here we demonstrate proof that alloying of the encapsulated nanowire is an additional approach to tuning of the magnetic properties of these structures by synthesis of radial-carbon-nanotube structures with γ-FeNi encapsulated nanowires.
Collapse
Affiliation(s)
- Filippo S Boi
- School of Physics and Astronomy, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
| | | | | | | | | |
Collapse
|
10
|
Lisunova Y, Heidler J, Levkivskyi I, Gaponenko I, Weber A, Caillier C, Heyderman LJ, Kläui M, Paruch P. Optimal ferromagnetically-coated carbon nanotube tips for ultra-high resolution magnetic force microscopy. NANOTECHNOLOGY 2013; 24:105705. [PMID: 23426040 DOI: 10.1088/0957-4484/24/10/105705] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Using single-walled carbon nanotubes homogeneously coated with ferromagnetic metal as ultra-high resolution magnetic force microscopy probes, we investigate the key image formation parameters and their dependence on coating thickness. The crucial step of introducing molecular beam epitaxy for deposition of the magnetic coating allows highly controlled fabrication of tips with small magnetic volume, while retaining high magnetic anisotropy and prolonged lifetime characteristics. Calculating the interaction between the tips and a magnetic sample, including hitherto neglected thermal noise effects, we show that optimal imaging is achieved for a finite, intermediate-thickness magnetic coating, in excellent agreement with experimental observations. With such optimal tips, we demonstrate outstanding resolution, revealing sub-10 nm domains in hard magnetic samples, and non-perturbative imaging of nanoscale spin structures in soft magnetic materials, all at ambient conditions with no special vacuum, temperature or humidity controls.
Collapse
Affiliation(s)
- Y Lisunova
- DPMC-MaNEP, University of Geneva, 24 Quai Ernest-Ansermet, 1211 Geneva 4, Switzerland.
| | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Maletinsky P, Hong S, Grinolds MS, Hausmann B, Lukin MD, Walsworth RL, Loncar M, Yacoby A. A robust scanning diamond sensor for nanoscale imaging with single nitrogen-vacancy centres. NATURE NANOTECHNOLOGY 2012; 7:320-4. [PMID: 22504708 DOI: 10.1038/nnano.2012.50] [Citation(s) in RCA: 187] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 03/13/2012] [Indexed: 05/05/2023]
Abstract
The nitrogen-vacancy defect centre in diamond has potential applications in nanoscale electric and magnetic-field sensing, single-photon microscopy, quantum information processing and bioimaging. These applications rely on the ability to position a single nitrogen-vacancy centre within a few nanometres of a sample, and then scan it across the sample surface, while preserving the centre's spin coherence and readout fidelity. However, existing scanning techniques, which use a single diamond nanocrystal grafted onto the tip of a scanning probe microscope, suffer from short spin coherence times due to poor crystal quality, and from inefficient far-field collection of the fluorescence from the nitrogen-vacancy centre. Here, we demonstrate a robust method for scanning a single nitrogen-vacancy centre within tens of nanometres from a sample surface that addresses both of these concerns. This is achieved by positioning a single nitrogen-vacancy centre at the end of a high-purity diamond nanopillar, which we use as the tip of an atomic force microscope. Our approach ensures long nitrogen-vacancy spin coherence times (∼75 µs), enhanced nitrogen-vacancy collection efficiencies due to waveguiding, and mechanical robustness of the device (several weeks of scanning time). We are able to image magnetic domains with widths of 25 nm, and demonstrate a magnetic field sensitivity of 56 nT Hz(-1/2) at a frequency of 33 kHz, which is unprecedented for scanning nitrogen-vacancy centres.
Collapse
Affiliation(s)
- P Maletinsky
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Zhu M, Diao G. Review on the progress in synthesis and application of magnetic carbon nanocomposites. NANOSCALE 2011; 3:2748-67. [PMID: 21611651 DOI: 10.1039/c1nr10165j] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
This review focuses on the synthesis and application of nanostructured composites containing magnetic nanostructures and carbon-based materials. Great progress in fabrication of magnetic carbon nanocomposites has been made by developing methods including filling process, template-based synthesis, chemical vapor deposition, hydrothermal/solvothermal method, pyrolysis procedure, sol-gel process, detonation induced reaction, self-assembly method, etc. The applications of magnetic carbon nanocomposites expanded to a wide range of fields such as environmental treatment, microwave absorption, magnetic recording media, electrochemical sensor, catalysis, separation/recognization of biomolecules and drug delivery are discussed. Finally, some future trends and perspectives in this research area are outlined.
Collapse
Affiliation(s)
- Maiyong Zhu
- College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, PR China
| | | |
Collapse
|
13
|
Martínez L, Tello M, Díaz M, Román E, Garcia R, Huttel Y. Aspect-ratio and lateral-resolution enhancement in force microscopy by attaching nanoclusters generated by an ion cluster source at the end of a silicon tip. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2011; 82:023710. [PMID: 21361604 DOI: 10.1063/1.3556788] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
One of the factors that limit the spatial resolution in atomic force microscopy (AFM) is the physical size of the probe. This limitation is particularly severe when the imaged structures are comparable in size to the tip's apex. The resolution in the AFM is usually enhanced by using sharp tips with high aspect ratios. In the present paper we propose an approach to modify AFM tips that consists of depositing nanoclusters on standard silicon tips. We show that the use of those tips leads to atomic force microscopy images of higher aspect ratios and spatial resolution. The present approach has two major properties. It provides higher aspect-ratio images of nanoscale objects and, at the same time, enables to functionalize the AFM tips by depositing nanoparticles with well-controlled chemical composition.
Collapse
Affiliation(s)
- L Martínez
- Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | | | | | | | | | | |
Collapse
|