The Experts below are selected from a list of 32607 Experts worldwide ranked by ideXlab platform
Ronald L Walsworth - One of the best experts on this subject based on the ideXlab platform.
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geometric phase Magnetometry using a solid state spin
Nature Communications, 2018Co-Authors: K Arai, Chinmay Belthangady, David Glenn, Huiliang Zhang, Ronald L WalsworthAbstract:A key challenge of Magnetometry lies in the simultaneous optimization of magnetic field sensitivity and maximum field range. In interferometry-based Magnetometry, a quantum two-level system acquires a dynamic phase in response to an applied magnetic field. However, due to the 2π periodicity of the phase, increasing the coherent interrogation time to improve sensitivity reduces field range. Here we introduce a route towards both large magnetic field range and high sensitivity via measurements of the geometric phase acquired by a quantum two-level system. We experimentally demonstrate geometric-phase Magnetometry using the electronic spin associated with the nitrogen vacancy (NV) color center in diamond. Our approach enables unwrapping of the 2π phase ambiguity, enhancing field range by 400 times. We also find additional sensitivity improvement in the nonadiabatic regime, and study how geometric-phase decoherence depends on adiabaticity. Our results show that the geometric phase can be a versatile tool for quantum sensing applications. When performing interferometry-based Magnetometry, there is generally a trade-off between sensitivity and range. Here, instead, the authors demonstrate a geometric-phase-based protocol which allows a 400-fold enhancement in static magnetic field range with a single NV-centre without reducing sensitivity.
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Geometric phase Magnetometry using a solid-state spin
Nature Communications, 2018Co-Authors: K Arai, David R Glenn, Chinmay Belthangady, Jay Lee, Ronald L WalsworthAbstract:Magnetometry is a powerful technique for the non-invasive study of biological and physical systems. A key challenge lies in the simultaneous optimization of magnetic field sensitivity and maximum field range. In interferometry-based Magnetometry, a quantum two-level system acquires a dynamic phase in response to an applied magnetic field. However, due to the 2{\pi} periodicity of the phase, increasing the coherent interrogation time to improve sensitivity results in reduced field range. Here we introduce a route towards both large magnetic field range and high sensitivity via measurements of the geometric phase acquired by a quantum two-level system. We experimentally demonstrate geometric-phase Magnetometry using the optically addressable electronic spin associated with the nitrogen vacancy (NV) color center in diamond. Our approach enables unwrapping of the 2{\pi} phase ambiguity, decoupling of magnetic field range from sensitivity, and enhancement of the field range by about 400 times. We also find additional improvement in sensitivity in the nonadiabatic regime, and study how geometric-phase decoherence depends on adiabaticity. Our results show that the geometric phase can be a versatile tool for quantum sensing applications.
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Berry phase Magnetometry using a single electronic spin in diamond
Bulletin of the American Physical Society, 2015Co-Authors: K Arai, Chinmay Belthangady, Ronald L WalsworthAbstract:eld sensing using Berry phase. In the conventional Ramsey interferometry, an NV spin accumulates dynamic phase proportional to the Larmor frequency. This approach provides high sensitivity in exchange for the dynamic-range due to 2pi phase ambiguity. Our approach, in which the magnetic eld is encoded in the Berry phase of the spin, can unwrap this ambiguity due to a chirped Magnetometry curve. This work will provide a new modality not only for Magnetometry but also for thermometry and electrometry using solid-state spins.
Sebastian T. B. Goennenwein - One of the best experts on this subject based on the ideXlab platform.
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Theoretical model for torque differential Magnetometry
arXiv: Materials Science, 2014Co-Authors: Akashdeep Kamra, Michael Schreier, Hans Huebl, Sebastian T. B. GoennenweinAbstract:We present a generic theoretical model for torque differential Magnetometry (TDM) - an experimental method for determining the magnetic properties of a magnetic specimen by recording the resonance frequency of a mechanical oscillator, on which the magnetic specimen has been mounted, as a function of the applied magnetic field. The effective stiffness change, and hence the resonance frequency shift, of the oscillator due to the magnetic torque on the specimen is calculated for an arbitrary magnetic free energy density characterizing the specimen, as well as the relative orientation of the applied magnetic field, the specimen and the oscillator. Our calculations agree well with published experimental data. The theoretical model presented here allows to take full advantage of TDM as an efficient Magnetometry method.
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Theoretical model for torque differential Magnetometry of single-domain magnets
Physical Review B - Condensed Matter and Materials Physics, 2014Co-Authors: Akashdeep Kamra, Michael Schreier, Hans Huebl, Sebastian T. B. GoennenweinAbstract:We present a generic theoretical model for torque differential Magnetometry (TDM) - an experimental method for determining the magnetic properties of a magnetic specimen by recording the resonance frequency of a mechanical oscillator, on which the magnetic specimen has been mounted, as a function of the applied magnetic field. The effective stiffness change, and hence the resonance frequency shift, of the oscillator due to the magnetic torque on the specimen is calculated for an arbitrary magnetic free energy density characterizing the specimen, as well as the relative orientation of the applied magnetic field, the specimen and the oscillator. Our calculations agree well with published experimental data. The theoretical model presented here allows to take full advantage of TDM as an efficient Magnetometry method.
Suchada Rajca - One of the best experts on this subject based on the ideXlab platform.
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triplet s 1 ground state aminyl diradical
Journal of the American Chemical Society, 2007Co-Authors: Andrzej Rajca, Maren Pink, Kouichi Shiraishi, Suchada RajcaAbstract:Aminyl diradical, which is stable in solution at low temperatures, is prepared. EPR spectra and SQUID Magnetometry indicate that the diradical is planar and it possesses triplet ground state, with strong ferromagnetic coupling.
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Triplet (S = 1) Ground State Aminyl Diradical
Journal of the American Chemical Society, 2007Co-Authors: Andrzej Rajca, Maren Pink, Kouichi Shiraishi, Suchada RajcaAbstract:Aminyl diradical, which is stable in solution at low temperatures, is prepared. EPR spectra and SQUID Magnetometry indicate that the diradical is planar and it possesses triplet ground state, with strong ferromagnetic coupling.
M R Freeman - One of the best experts on this subject based on the ideXlab platform.
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Optomechanical torque Magnetometry
2016 Conference on Lasers and Electro-Optics (CLEO), 2016Co-Authors: Marcelo Wu, Nathanael L.y. Wu, Tayyaba Firdous, Joseph E. Losby, Fatemeh Fani Sani, M R Freeman, Paul E BarclayAbstract:A photonic crystal split-beam cavity capable of optomechanical detection of magnetic torques from a nanomagnetic permalloy film is presented. The magnetic response of the magnetometer coupled to torsional mechanical vibrations is observed in ambient conditions.
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Optomechanical torque Magnetometry
International Conference on Optical MEMS and Nanophotonics, 2016Co-Authors: Marcelo Wu, Nathanael L.y. Wu, Tayyaba Firdous, Joseph E. Losby, Fatemeh Fani Sani, M R Freeman, Paul E BarclayAbstract:A brief history, the current state, and future directions of spin mechanics are presented.
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Nanomechanical torque Magnetometry of an individual aggregate of ∼350 nanoparticles1
Canadian Journal of Physics, 2015Co-Authors: Tayyaba Firdous, D. Vick, Joseph E. Losby, Fatemeh Fani Sani, M. Belov, A. Mcdermott, D. A. Bazylinski, T. Prozorov, D. K. Potter, M R FreemanAbstract:The measurements of magnetic hysteresis for aggregates of nanoparticles deposited on a surface are reported. Magnetite nanoparticles derived from magnetotactic bacteria are studied using nanomechanical torque Magnetometry. The nanoparticles are deposited on high-stress Si3N4 membranes, to allow inspection by electron microscopy, followed by focused ion-beam milling of torsional resonators precisely located to capture selected aggregates within the membrane area. Torque Magnetometry is performed using the resonators. We investigate also the magnetic torque-driven AC resonant modes of the modified supporting membrane. The observations are compared to numerical simulations of the mechanical modes, and to micromagnetic modeling of the hysteresis of a specific measured cluster of ∼350 nanoparticles.
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Nanotorsional resonator torque Magnetometry
Applied Physics Letters, 2010Co-Authors: J.p. Davis, Jeffrey A Burgess, D. Vick, D. C. Fortin, W. K. Hiebert, M R FreemanAbstract:Magnetic torque is used to actuate nano-torsional resonators, which are fabricated by focused-ion-beam milling of permalloy coated silicon nitride membranes. Optical interferometry is used to measure the mechanical response of two torsion modes at resonance, which is proportional to the magnetization vector of the nanomagnetic volume. By varying the bias magnetic field, the magnetic behavior can be measured with excellent sensitivity ($\approx 10^8 \mu_B$) for single magnetic elements.
K Arai - One of the best experts on this subject based on the ideXlab platform.
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geometric phase Magnetometry using a solid state spin
Nature Communications, 2018Co-Authors: K Arai, Chinmay Belthangady, David Glenn, Huiliang Zhang, Ronald L WalsworthAbstract:A key challenge of Magnetometry lies in the simultaneous optimization of magnetic field sensitivity and maximum field range. In interferometry-based Magnetometry, a quantum two-level system acquires a dynamic phase in response to an applied magnetic field. However, due to the 2π periodicity of the phase, increasing the coherent interrogation time to improve sensitivity reduces field range. Here we introduce a route towards both large magnetic field range and high sensitivity via measurements of the geometric phase acquired by a quantum two-level system. We experimentally demonstrate geometric-phase Magnetometry using the electronic spin associated with the nitrogen vacancy (NV) color center in diamond. Our approach enables unwrapping of the 2π phase ambiguity, enhancing field range by 400 times. We also find additional sensitivity improvement in the nonadiabatic regime, and study how geometric-phase decoherence depends on adiabaticity. Our results show that the geometric phase can be a versatile tool for quantum sensing applications. When performing interferometry-based Magnetometry, there is generally a trade-off between sensitivity and range. Here, instead, the authors demonstrate a geometric-phase-based protocol which allows a 400-fold enhancement in static magnetic field range with a single NV-centre without reducing sensitivity.
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Geometric phase Magnetometry using a solid-state spin
Nature Communications, 2018Co-Authors: K Arai, David R Glenn, Chinmay Belthangady, Jay Lee, Ronald L WalsworthAbstract:Magnetometry is a powerful technique for the non-invasive study of biological and physical systems. A key challenge lies in the simultaneous optimization of magnetic field sensitivity and maximum field range. In interferometry-based Magnetometry, a quantum two-level system acquires a dynamic phase in response to an applied magnetic field. However, due to the 2{\pi} periodicity of the phase, increasing the coherent interrogation time to improve sensitivity results in reduced field range. Here we introduce a route towards both large magnetic field range and high sensitivity via measurements of the geometric phase acquired by a quantum two-level system. We experimentally demonstrate geometric-phase Magnetometry using the optically addressable electronic spin associated with the nitrogen vacancy (NV) color center in diamond. Our approach enables unwrapping of the 2{\pi} phase ambiguity, decoupling of magnetic field range from sensitivity, and enhancement of the field range by about 400 times. We also find additional improvement in sensitivity in the nonadiabatic regime, and study how geometric-phase decoherence depends on adiabaticity. Our results show that the geometric phase can be a versatile tool for quantum sensing applications.
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Berry phase Magnetometry using a single electronic spin in diamond
Bulletin of the American Physical Society, 2015Co-Authors: K Arai, Chinmay Belthangady, Ronald L WalsworthAbstract:eld sensing using Berry phase. In the conventional Ramsey interferometry, an NV spin accumulates dynamic phase proportional to the Larmor frequency. This approach provides high sensitivity in exchange for the dynamic-range due to 2pi phase ambiguity. Our approach, in which the magnetic eld is encoded in the Berry phase of the spin, can unwrap this ambiguity due to a chirped Magnetometry curve. This work will provide a new modality not only for Magnetometry but also for thermometry and electrometry using solid-state spins.