Related papers: Slowly generated anomalously large nuclear field i…
Nuclear spin relaxation is studied in n-GaAs thick layers and microcavity samples with different electron densities. We reveal that both in metallic samples where electrons are free and mobile, and in insulating samples, where electrons are…
We show that the spin-lattice relaxation in n-type insulating GaAs is dramatically accelerated at low magnetic fields. The origin of this effect, that cannot be explained in terms of well-known diffusion-limited hyperfine relaxation, is…
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…
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…
A new method for local dynamic nuclear polarization is demonstrated in a GaAs/AlGaAs heterostructure at the Landau level filling factor $\nu=3$. Using a narrow channel sample, where the width varies stepwise along the electron flow, we find…
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…
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…
Photoluminescence polarization is experimentally studied for samples with (In,Ga)As/GaAs selfassembled quantum dots in transverse magnetic field (Hanle effect) under slow modulation of the excitation light polarization from fractions of Hz…
We applied the recently developed technique of force-detected nuclear magnetic resonance (NMR) to observe 71Ga, 69Ga, and 75As in GaAs. The nuclear spin-lattice relaxation time is 21$\pm$5 min for 69Ga at $\sim 5$ K and 4.6 Tesla. We have…
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…
We theoretically study the dynamic polarization of lattice nuclear spins in GaAs double quantum dots containing two electrons. In our prior work [Phys. Rev. Lett. 104, 226807 (2010)] we identified three regimes of long-term dynamics,…
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…
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…
We theoretically investigate the controlled dynamic polarization of lattice nuclear spins in GaAs double quantum dots containing two electrons. Three regimes of long-term dynamics are identified, including the build up of a large difference…
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…
The hyperfine field from dynamically polarized nuclei in n-GaAs is very spatially inhomogeneous, as the nu- clear polarization process is most efficient near the randomly-distributed donors. Electrons with polarized spins traversing the…
We discuss the implications of a small indium content (3%) in a GaAs epilayer on the electron- and nuclear-spin relaxation due to enhanced quadrupolar effects induced by the strain. Using the weakly perturbative spin-noise spectroscopy, we…
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…
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…
Current-induced electron spin polarization is shown to produce nuclear hyperpolarization through dynamic nuclear polarization. Saturated fields of several millitesla are generated upon the application of electric field over a timescale of a…