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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

A room temperature nuclear magnetic resonance force microscope (MRFM), fitted in a $^1$Tesla electromagnet, is used to measure the nuclear spin relaxation of $^1$H in a micron-size (70ng) crystal of ammonium sulfate. NMR sequences,…

Condensed Matter · Physics 2009-10-31 O. Klein , V. V. Naletov , H. Alloul

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

Nuclear spin polarization dynamics are measured in optically pumped individual GaAs/AlGaAs interface quantum dots by detecting the time-dependence of the Overhauser shift in photoluminescence (PL) spectra. Long nuclear polarization decay…

Spin-lattice relaxation of the nuclear spin system in p-type GaAs is studied using a three-stage experimental protocol including optical pumping and measuring the difference of the nuclear spin polarization before and after a dark interval…

Other Condensed Matter · Physics 2018-05-02 M. Kotur , R. I. Dzhioev , M. Vladimirova , R. V. Cherbunin , P. S. Sokolov , D. R. Yakovlev , M. Bayer , D. Suter , K. V. Kavokin

The study of nuclear magnetic resonance and nuclear spin-lattice relaxation was conducted in an asymmetrically doped to $n\sim1.8\times10^{11}$ cm$^{-2}$ 16 nm AlAs quantum well grown in the $[001]$-direction. Dynamic polarization of…

Mesoscale and Nanoscale Physics · Physics 2016-12-22 A. V. Shchepetilnikov , D. D. Frolov , Yu. A. Nefyodov , I. V. Kukushkin , D. S. Smirnov , L. Tiemann , C. Reichl , W. Dietsche , W. Wegscheider

We use time-resolved detection of the Hanle effect and polarized photoluminescence with dark intervals to investigate the buildup and decay of the spin polarization of nuclei interacting with donor-bound electrons in $n$-doped GaAs. Strong…

Mesoscale and Nanoscale Physics · Physics 2019-02-21 P. S. Sokolov , M. Yu. Petrov , K. V. Kavokin , M. S. Kuznetsova , S. Yu. Verbin , I. Ya. Gerlovin , D. R. Yakovlev , M. Bayer

Nuclear spin-lattice relaxation times are measured on copper using magnetic resonance force microscopy performed at temperatures down to 42 mK. The low temperature is verified by comparison with the Korringa relation. Measuring spin-lattice…

A method for high-field optically detected nuclear magnetic resonance (ODNMR) is developed sensitive to 10**8 nuclei. Nuclear spin transitions are induced using a radio frequency coil and detected through Faraday rotation spectroscopy.…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 M. Poggio , D. D. Awschalom

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

Optically pumped nuclear magnetic resonance (OPNMR) measurements were performed in two different electron-doped multiple quantum well samples near the fractional quantum Hall effect ground state nu=1/3. Below 0.5K, the spectra provide…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 N. N. Kuzma , P. Khandelwal , S. E. Barrett , L. N. Pfeiffer , K. W. West

The dynamic polarization of nuclear spins interacting with resident electrons under resonant excitation of trions is studied in a nominally undoped GaAs/(Al,Ga)As quantum well. Unlike in common time-resolved pump-probe techniques, we used a…

Mesoscale and Nanoscale Physics · Physics 2018-11-28 M. Kotur , F. Saeed , R. W. Mocek , V. L. Korenev , I. A. Akimov , A. S. Bhatti , D. R. Yakovlev , D. Suter , M. Bayer

The nuclear spin fluctuations (NSF) as well as the dynamic nuclear polarization (DNP) and their effects on the electron spins in negatively charged (In,Ga)As/GaAs quantum dots have been studied by polarized pump-probe and photoluminescence…

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…

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

The dynamic polarization of nuclear spins by photoexcited electrons is studied in a high quality GaAs/AlGaAs quantum well. We find a surprisingly high efficiency of the spin transfer from the electrons to the nuclei as reflected by a…

Mesoscale and Nanoscale Physics · Physics 2017-11-15 R. W. Mocek , V. L. Korenev , M. Bayer , M. Kotur , R. I. Dzhioev , D. O. Tolmachev , G. Cascio , K. V. Kavokin , D. Suter

This study investigated the formation and relaxation dynamics of nuclear spin polarization in three Al$_x$Ga$_{1-x}$As bulk samples with different aluminum concentrations $x$ of 0.00, 0.05, and 0.15. The time-resolved Kerr rotation…

Materials Science · Physics 2026-02-20 A. Shen , J. Chen , R. Kaji , S. Yamamoto , H. Sasakura , T. Uemura , S. Adachi

We present nuclear spin relaxation measurements in GaAs epilayers using a new pump-probe technique in all-electrical, lateral spin-valve devices. The measured T1 times agree very well with NMR data available for T > 1 K. However, the…

Mesoscale and Nanoscale Physics · Physics 2012-08-24 D. Kölbl , D. M. Zumbühl , A. Fuhrer , G. Salis , S. F. Alvarado

When probing nuclear spins in materials on the nanometer scale, random fluctuations of the spin polarization will exceed the mean Boltzmann polarization for sample volumes below about (100nm)^3. In this work, we use magnetic resonance force…

Mesoscale and Nanoscale Physics · Physics 2008-01-14 C. L. Degen , M. Poggio , H. J. Mamin , D. Rugar

The spin dynamics of localized donor-bound electrons interacting with the nuclear spin ensemble in $n$-doped GaAs epilayers is studied using nuclear spin polarization by light with modulated circular polarization. We show that the observed…

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