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Related papers: Optically-patterned nuclear doughnuts in GaAs/MnAs…

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We exploit ferromagnetic imprinting to create complex laterally defined regions of nuclear spin polarization in lithographically patterned MnAs/GaAs epilayers grown by molecular beam epitaxy (MBE). A time-resolved Kerr rotation microscope…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 J. Stephens , R. K. Kawakami , J. Berezovsky , M. Hanson , D. P. Shepherd , A. C. Gossard , D. D. Awschalom

We study light-induced nuclear spin-polarization in a thin film of Ga1-xMnxAs (x 0.04), a dilute ferromagnetic semiconductor, grown on a GaAs substrate. High-field inductively-detected Ga-71 NMR was performed with samples immersed in…

Irradiating a semiconductor with circularly polarized light creates spin-polarized charge carriers. If the material contains atoms with non-zero nuclear spin, they interact with the electron spins via the hyperfine coupling. Here, we…

Mesoscale and Nanoscale Physics · Physics 2016-09-09 Raphael W. Mocek , Danil O. Tolmachev , Giovanni Cascio , Dieter Suter

Understanding and manipulating spin polarization and transport in the vicinity of semiconductor-hosted defects is a problem of present technological and fundamental importance. Here, we use high-field magnetic resonance to monitor the…

Mesoscale and Nanoscale Physics · Physics 2014-01-14 Yunpu Li , Jonathan P. King , Jeffrey A. Reimer , Carlos A. Meriles

We investigate the dynamic polarization of nuclear spins in a nominally undoped GaAs/Al$_{0.35}$Ga$_{0.65}$As quantum well using two complementary experimental approaches: time-resolved Kerr rotation and optical orientation measurements of…

Mesoscale and Nanoscale Physics · Physics 2025-12-24 M. Kotur , D. Kudlacik , N. E. Kopteva , E. Kirstein , D. R. Yakovlev , K. V. Kavokin , M. Bayer

We investigate the dynamic nuclear polarization from the hyperfine interaction between nonequilibrium electronic spins and nuclear spins coupled to them in semiconductor nanostructures. We derive the time and position dependence of the…

Materials Science · Physics 2007-05-23 Ionel Tifrea , Michael E. Flatte

We study the optically pumped nuclear spin polarization in a single GaAs/AlGaAs quantum well in the quantum Hall system. We apply resistive detection via the contact hyperfine interaction, which provides high sensitivity and selectivity, to…

Mesoscale and Nanoscale Physics · Physics 2013-06-24 K. Akiba , T. Yuge , S. Kanasugi , K. Nagase , Y. Hirayama

We demonstrate one-dimensional nuclear magnetic resonance imaging of the semiconductor GaAs with 170 nanometer slice separation and resolve two regions of reduced nuclear spin polarization density separated by only 500 nanometers. This is…

Instrumentation and Detectors · Physics 2009-11-07 Kent R. Thurber , Lee E. Harrell , Doran D. Smith

Magnetic noise of atomic nuclear spins is a major problem for solid state spin qubits. Highly-polarized nuclei would not only overcome this obstacle, but also make nuclear spins a useful quantum information resource. However, achieving…

We measure the statistical polarization of quadrupolar nuclear spins in a sub-micrometer (0.6 um^3) particle of GaAs using magnetic resonance force microscopy. The crystalline sample is cut out of a GaAs wafer and attached to a…

Mesoscale and Nanoscale Physics · Physics 2016-11-25 Fei Xue , D. P. Weber , P. Peddibhotla , M. Poggio

We find that photoexcited electrons in an n-GaAs epilayer rapidly (< 50 ps) spin-polarize due to the proximity of an epitaxial ferromagnetic metal. Comparison between MnAs/GaAs and Fe/GaAs structures reveals that this coherent spin…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 R. J. Epstein , I. Malajovich , R. K. Kawakami , Y. Chye , M. Hanson , P. M. Petroff , A. C. Gossard , D. D. Awschalom

Recently reported optical nuclear orientation in the $n$-doped GaAs microcavity under pumping in nominal transparency region of the crystal [Appl. Phys. Lett. $\mathbf{106}$, 242405 (2015)] has arisen a number of questions, the main of them…

We report the observation of nuclear magnetic resonance (NMR) in a ferromagnet-semiconductor heterostructure in the presence of a spin-polarized current. Spin-polarized electrons injected from a metallic ferromagnet generate a large nuclear…

Condensed Matter · Physics 2009-11-10 J. Strand , B. D. Schultz , A. F. Isakovic , X. Lou , C. J. Palmstrom , P. A. Crowell

We theoretically investigate dynamic nuclear spin polarization in a self-assembled quantum dot pumped optically by two laser beams. With the assumption that a noncollinear interaction between the hole spin and nuclear spins leads to nuclear…

Mesoscale and Nanoscale Physics · Physics 2013-06-07 Xiao-Feng Shi

We polarize nuclear spins in a GaAs double quantum dot by controlling two-electron spin states near the anti-crossing of the singlet (S) and m_S=+1 triplet (T+) using pulsed gates. An initialized S state is cyclically brought into resonance…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 J. R. Petta , J. M. Taylor , A. C. Johnson , A. Yacoby , M. D. Lukin , C. M. Marcus , M. P. Hanson , A. C. Gossard

We report on the dynamic nuclear polarization of a single charge-tunable self-assembled InAs/GaAs quantum dot in a longitudinal magnetic field of $\sim$0.2T. The hyperfine interaction between the optically oriented electron and nuclei spins…

We report optical orientation experiments in individual, strain free GaAs quantum dots in AlGaAs grown by droplet epitaxy. Circularly polarized optical excitation yields strong circular polarization of the resulting photoluminescence at 4K.…

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

The paper reports optical orientation experiments performed in the narrow GaAs/AlGaAs quantum wells doped with Mn. We experimentally demonstrate a control over the spin polarization by means of the optical orientation via the…

Mesoscale and Nanoscale Physics · Physics 2016-09-02 P. V. Petrov , I. A. Kokurin , Yu. L. Ivanov , N. S. Averkiev , R. P. Campion , B. L. Gallagher , P. M. Koenraad , A. Yu. Silov

We exploit spin noise spectroscopy (SNS) to directly observe build-up of dynamic nuclear polarization and relaxation of a perturbed nuclear spin-system to its equilibrium state in a single-shot experiment. The SNS experiments were performed…

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