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Related papers: Dynamic Nuclear Polarization in a Quantum Hall Cor…

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We have observed millisecond-long coherent evolution of nuclear spins in a quantum wire at 1.2 K. Local, all-electrical manipulation of nuclear spins is achieved by dynamic nuclear polarization in the breakdown regime of the Integer Quantum…

Mesoscale and Nanoscale Physics · Physics 2009-10-01 A. Corcoles , C. J. B. Ford , M. Pepper , G. A. C. Jones , H. E. Beere , D. A. Ritchie

The central-spin problem, in which an electron spin interacts with a nuclear spin bath, is a widely studied model of quantum decoherence. Dynamic nuclear polarization (DNP) occurs in central spin systems when electronic angular momentum is…

Dynamic nuclear polarization (DNP) is an out-of-equilibrium method for generating non-thermal spin polarization which provides large signal enhancements in modern diagnostic methods based on nuclear magnetic resonance. A particular instance…

We investigate dynamic nuclear polarization in quantum point contacts (QPCs) in the integer and fractional quantum Hall regimes. Following the application of a dc bias, fractional plateaus in the QPC shift symmetrically about half filling…

Mesoscale and Nanoscale Physics · Physics 2014-11-20 A. Kou , D. T. McClure , C. M. Marcus , L. N. Pfeiffer , K. W. West

We study dynamic polarization and resistive detection of nuclear spins in a semiconductor quantum dot (QD) under the Kondo effect regime. We find that the differential conductance spectra of the QD exhibit hysteresis under the Kondo effect…

Mesoscale and Nanoscale Physics · Physics 2013-02-19 Minoru Kawamura , Daniel Gottwald , Keiji Ono , Tomoki Machida , Kimitoshi Kono

We investigate the dynamic nuclear polarization process by frequently injecting polarized electron spins into a quantum dot. Due to the suppression of the direct dipolar and indirect electron-mediated nuclear spin interactions, by the…

Mesoscale and Nanoscale Physics · Physics 2016-07-26 Na Wu , Wenkui Ding , Anqi Shi , Wenxian Zhang

There has been much renewed interest in dynamic nuclear polarization (DNP), particularly in the context of solid state biomolecular NMR and more recently dissolution DNP techniques for liquids. This paper reviews the role of spin diffusion…

Other Condensed Matter · Physics 2009-04-01 Chandrasekhar Ramanathan

We propose a new method for dynamic nuclear polarisation in a quasi one-dimensional quantum wire utilising the spin-orbit interaction, the hyperfine interaction, and a finite source-drain potential difference. In contrast with current…

Mesoscale and Nanoscale Physics · Physics 2008-03-05 V. Tripathi , A. C. H. Cheung , N. R. Cooper

Dynamic nuclear polarisation (DNP) refers to a class of techniques used to increase the signal in nuclear magnetic resonance measurements by transferring spin polarisation from ensembles of highly polarised electrons to target nuclear…

Quantum Physics · Physics 2020-12-24 L. T. Hall , D. A. Broadway , A. Stacey , D. A. Simpson , J-P. Tetienne , L. C. L. Hollenberg

Using a conventional Hall-bar geometry with a micro-metal strip on top of the surface, we demonstrate an electrical coherent control of nuclear spins in an AlGaAs/GaAs semiconductor heterostructure. A breakdown of integer quantum Hall (QH)…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 H. Takahashi , M. Kawamura , S. Masubuchi , K. Hamaya , T. Machida , Y. Hashimoto , S. Katsumoto

The quantum Hall effect, which exhibits a number of unusual properties, is studied in a gated 1000-nm-thick HgTe film, nominally a three-dimensional system. A weak zero plateau of Hall resistance, accompanied by a relatively small value of…

Mesoscale and Nanoscale Physics · Physics 2024-09-17 M. L. Savchenko , D. A. Kozlov , S. S. Krishtopenko , N. N. Mikhailov , Z. D. Kvon , A. Pimenov , D. Weiss

We investigate in detail, using both analytical and numerical tools, the decoherence of electron spins in quantum dots (QDs) coupled to a bath of nuclear spins in magnetic fields or with various initial bath polarizations, focusing on the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Wenxian Zhang , V. V. Dobrovitski , K. A. Al-Hassanieh , E. Dagotto , B. N. Harmon

Dynamic nuclear polarization (DNP) involves a polarization transfer from unpaired electrons to hyperfine coupled nuclei and can increase the sensitivity of nuclear magnetic resonance (NMR) signals by several orders of magnitude. The…

Chemical Physics · Physics 2024-07-16 Gevin von Witte , Sebastian Kozerke , Matthias Ernst

We observe variation in the resistively-detected nuclear magnetic resonance (RDNMR) lineshapes in quantum Hall breakdown. The breakdown is locally occurred in a gate-defined quantum point contact (QPC) region. Of particular interest is the…

Mesoscale and Nanoscale Physics · Physics 2017-06-14 M. H. Fauzi , A. Singha , M. F. Sahdan , M. Takahashi , K. Sato , K. Nagase , B. Muralidharan , Y. Hirayama

Chemically induced dynamic nuclear polarization is a signature of spin order appearing in many photosynthetic reaction centers. Such polarization, significantly enhanced above thermal equilibrium, is known to result from the nuclear spin…

Quantum Physics · Physics 2015-06-12 I. K. Kominis

Dynamic nuclear polarization transfers spin polarization from electrons to nuclei. We have achieved this by a new method, simultaneously exciting transitions of electronic and nuclear spins. The efficiency of this technique improves with…

Quantum Physics · Physics 2008-09-11 G. W. Morley , K. Porfyrakis , A. Ardavan , J. van Tol

Coupled electron-nuclear spins represent a promising quantum system, where the optically induced electron spin polarization can be dynamically transferred to nuclear spins via the hyperfine interaction. Most experiments on dynamic nuclear…

Materials Science · Physics 2026-01-13 A. N. Anisimov , A. V. Poshakinskiy , G. V. Astakhov

Nuclear-spin diffusion in double quantum wells (QWs) is examined by using dynamic nuclear polarization (DNP) at a Landau level filling factor $\nu=2/3$ spin phase transition (SPT). The longitudinal resistance increases during the DNP of one…

Mesoscale and Nanoscale Physics · Physics 2015-04-01 T. Hatano , W. Kume , S. Watanabe , K. Akiba , K. Nagase , Y. Hirayama

At the spin transition point of $\nu=2/3$ quantum Hall states, nuclear spins in a two-dimensional electron gas are polarized by an electric current. Using GaAs/AlGaAs double-quantum-well samples, we first observed the spatial diffusion of…

Mesoscale and Nanoscale Physics · Physics 2014-01-14 Minh-Hai Nguyen , Shibun Tsuda , Daiju Terasawa , Akira Fukuda , Yangdong Zheng , Anju Sawada

Nuclear spin polarization is typically generated in GaAs quantum point contacts (QPCs) when an out-of-plane magnetic field gives rise to spin-polarized quantum Hall edge states, and a voltage bias drives transitions between the edge states…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 Y. Ren , W. Yu , S. M. Frolov , J. A. Folk , W. Wegscheider