Related papers: Dynamic nuclear polarization induced by hot electr…
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…
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…
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…
Spontaneous nuclear polarization is predicted in double quantum dots in the spin-blocked electron transport regime. The polarization results from an instability of the zero-polarization state when singlet and triplet electron energy levels…
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…
We have used gated GaAs/AlGaAs heterostructures to explore nonlinear transport between spin-resolved Landau level (LL) edge states over a submicron region of two-dimensional electron gas (2DEG). The current I flowing from one edge state to…
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…
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…
Direct dynamic nuclear polarization of 1H nuclei in frozen water and water-ethanol mixtures is demonstrated using silicon nanoparticles as the polarizing agent. Electron spins at dangling-bond sites near the silicon surface are identified…
Spin current perpendicular to the electric current is investigated around Landau level filling factor $\nu=3$ in a GaAs/AlGaAs two-dimensional electron system. Measurements of dynamic nuclear polarization in the vicinity of the edge of a…
Thermal measurements on a GaAs/AlGaAs heterostructure reveal that the state of the confined two-dimensional electrons dramatically affects the nuclear-spin diffusion near Landau level filling factor \nu=1. The experiments provide…
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…
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…
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 observe dynamic nuclear polarization in a GaAs double dot system using two electrons that are never exchanged with the reservoir. By periodically bringing the system to the mixing point where the singlet and the triplet T+ states are…
We investigate in micro-photoluminescence experiments the dynamical nuclear polarization in individual InGaAs quantum dots. Experiments carried out in an applied magnetic field of 2T show that the nuclear polarization achieved through the…
Dynamic Nuclear Polarization (DNP) is to date the most effective technique to increase the nuclear polarization up to a factor $100,000$ opening disruptive perspectives for medical applications. In DNP, the nuclear spins are driven to an -…
We demonstrate a new method for electrical manipulation of nuclear spins utilizing dynamic nuclear polarization induced by quantum Hall effect breakdown. Nuclear spins are polarized and detected through the hyperfine interaction between a…
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…
The concept of nuclear spin temperature has been a cornerstone of the theory of dynamic nuclear spin polarization by electrons in various semiconductor structures for decades. Still, it is not always applicable to strongly localized…