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Hyperfine interactions between electron and nuclear spins in the quantum Hall regime provide powerful means for manipulation and detection of nuclear spins. In this work we demonstrate that significant changes in nuclear spin polarization…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 Y. Q. Li , V. Umansky , K. von Klitzing , J. H. Smet

We show that in a quantum wire the spin-orbit interaction leads to a narrow spin resonance at low temperatures, even in the absence of an external magnetic field. A relatively weak dc magnetic field of a definite direction strongly…

Strongly Correlated Electrons · Physics 2010-08-09 Ar. Abanov , V. L. Pokrovsky , W. M. Saslow , P. Zhou

We implement a microscopic spin filter for cold fermionic atoms in a quantum point contact (QPC) and create fully spin-polarized currents while retaining conductance quantization. Key to our scheme is a near-resonant optical tweezer…

We present a detailed analytical and numerical analysis of the nuclear spin dynamics in parabolic quantum wells. The shallow potential of parabolic quantum wells permits substantial modification of the electronic wave function in small…

Materials Science · Physics 2009-11-10 I. Tifrea , Michael E. Flatte

A ring structure fabricated from GaAs is used to achieve interference of the net spin polarization of conduction band electrons. Optically polarized spins are split into two packets by passing through two arms of the ring in the diffusive…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Y. K. Kato , R. C. Myers , A. C. Gossard , D. D. Awschalom

We theoretically study the nuclear spin dynamics driven by electron transport and hyperfine interaction in an electrically-defined double quantum dot (DQD) in the Pauli-blockade regime. We derive a master-equation-based framework and show…

Mesoscale and Nanoscale Physics · Physics 2014-06-03 Martin J. A. Schuetz , Eric M. Kessler , Lieven M. K. Vandersypen , J. Ignacio Cirac , Geza Giedke

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

We report on the direct measurement of the electron spin splitting and the accompanying nuclear Overhauser (OH) field, and thus the underlying nuclear spin polarization (NSP) and fluctuation bandwidth, in a single InAs quantum dot under…

Mesoscale and Nanoscale Physics · Physics 2021-01-04 Aaron M. Ross , Allan S. Bracker , Michael K. Yakes , Daniel Gammon , L. J. Sham , Duncan G. Steel

In this work, we devise a fast and effective nuclear spin hyperpolarization scheme, which is in principle magnetic field and temperature independent. We use this scheme to experimentally demonstrate polarizations of up to 66% for phosphorus…

Nuclear spins are polarized electrically in a breakdown regime of an odd-integer quantum Hall effect (QHE). Electron excitation to the upper Landau subband with the opposite spin polarity flips nuclear spins through the hyperfine…

Mesoscale and Nanoscale Physics · Physics 2008-07-04 M. Kawamura , H. Takahashi , S. Masubuchi , Y. Hashimoto , S. Katsumoto , K. Hamaya , T. Machida

By placing changeable nanofabricated structures (wires, dots, etc.) on an atom mirror one can design guiding and trapping potentials for atoms. These potentials are similar to the electrostatic potentials which trap and guide electrons in…

Quantum Physics · Physics 2009-10-31 Joerg Schmiedmayer

All-electrical control of spin transport in nanostructures has been the central interest and chal- lenge of spin physics and spintronics. Here we demonstrate on-chip spin polarizing/filtering actions by driving the gate-defined one…

Mesoscale and Nanoscale Physics · Physics 2012-11-13 T. -M. Chen , M. Pepper , I. Farrer , G. A. C. Jones , D. A. Ritchie

We have studied hyperfine interactions between spin-polarized electrons and lattice nuclei in Al_0.1Ga_0.9As/GaAs quantum well (QW) heterostructures. The spin-polarized electrons are electrically injected into the semiconductor…

Materials Science · Physics 2009-11-11 J. Strand , X. Lou , C. Adelmann , B. D. Schultz , A. F. Isakovic , C. J. Palmstrom , P. A. Crowell

Polarization transfers are crucial building blocks in magnetic resonance experiments, i.e., they can be used to polarize insensitive nuclei and correlate nuclear spins in multidimensional NMR spectroscopy. The polarization can be…

Chemical Physics · Physics 2022-08-24 Zhenfeng Pang , Sheetal Jain , Chen Yang , Xueqian Kong , Kong Ooi Tan

Nuclear quadrupole interaction extends the limits imposed by hyperfine interaction on the spin coherence of the electron and nuclei in a quantum dot. The strain-induced nuclear quadrupole interaction suppresses the nuclear spin flip and…

Mesoscale and Nanoscale Physics · Physics 2008-04-01 R. I. Dzhioev , V. L. Korenev

We report electrical control of the spin polarization of InAs/GaAs self-assembled quantum dots (QDs) at room temperature. This is achieved by electrical injection of spin-polarized electrons from an Fe Schottky contact. The circular…

We measure the strength and the sign of hyperfine interaction of a heavy-hole with nuclear spins in single self-assembled quantum dots. Our experiments utilize the locking of a quantum dot resonance to an incident laser frequency to…

Mesoscale and Nanoscale Physics · Physics 2010-09-02 P. Fallahi , S. T. Yilmaz , A. Imamoglu

We study the dynamics of optically-induced nuclear spin polarization in a fluorine-doped ZnSe epilayer via time-resolved Kerr rotation. The nuclear polarization in the vicinity of a fluorine donor is induced by interaction with coherently…

Mesoscale and Nanoscale Physics · Physics 2016-02-24 F. Heisterkamp , E. Kirstein , A. Greilich , E. A. Zhukov , T. Kazimierczuk , D. R. Yakovlev , A. Pawlis , M. Bayer

Pulsed Dynamic Nuclear Polarization (DNP) is currently receiving substantial interest as a means to enhance the sensitivity of nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) by orders of magnitude. It has also…

Hyper-polarization of nuclear spins is crucial for advancing nuclear magnetic resonance (NMR) and quantum information technologies, as nuclear spins typically exhibit extremely low polarization at room temperature due to their small…

Quantum Physics · Physics 2025-05-20 Haiyang Li , Hao Liao , Ping Wang
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