Related papers: Landau level spin diode in a GaAs two dimensional …
We present numerical results for electron spin relaxation rates for single and laterally coupled double GaAs quantum dots in a perpendicular magnetic field. As source of spin relaxation we consider hyperfine interaction with the nuclear…
In the envelope-function approximation, interband transitions produced by electric fields are neglected. However, electric fields may lead to a spatially local ($k$-independent) coupling of band (internal, pseudospin) degrees of freedom.…
The effect of nuclear spins in Fe/GaAs all-electrical spin-injection devices is investigated. At temperatures below 50 K, strong modifications of the non-local spin signal are found that are characteristic for hyperfine coupling between…
The electronic states of lateral many electron quantum dots in high magnetic fields are analyzed in terms of energy and spin. In a regime with two Landau levels in the dot, several Coulomb blockade peaks are measured. A zig-zag pattern is…
We report the experimental observation of the spin-Hall effect in a two-dimensional (2D) hole system with Rashba spin-orbit coupling. The 2D hole layer is a part of a p-n junction light-emitting diode with a specially designed co-planar…
We study the spin-polarized $\nu=0$ Landau-level state of graphene. Due to the electron-hole attractive interaction, electrons and holes can bound into pairs. These pairs can then condense into a spin-triplet superfluid ground state: a spin…
For the realisation of scalable solid-state quantum-bit systems, spins in semiconductor quantum dots are promising candidates. A key requirement for quantum logic operations is a sufficiently long coherence time of the spin system.…
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 demonstrate a hole double quantum dot in an undoped GaAs/AlGaAs heterostructure. The interdot coupling can be tuned over a wide range, from formation of a large single dot to two well-isolated quantum dots. Using charge sensing, we show…
We report a study of suppressed spin dephasing for quasi-one-dimensional electron ensembles in wires etched into a GaAs/AlGaAs heterojunction system. Time-resolved Kerr-rotation measurements show a suppression that is most pronounced for…
We report measurements and calculations of the spin-polarization, induced by a parallel magnetic field, of interacting, dilute, two-dimensional electron systems confined to GaAs/AlGaAs heterostructures. The results reveal the crucial role…
We study the 3D topological insulators in the continuum by coupling spin-1/2 fermions to the Aharonov-Casher SU(2) gauge field. They exhibit flat Landau levels in which orbital angular momentum and spin are coupled with a fixed helicity.…
A recently discovered mechanism of electric dipole spin resonance, mediated by the hyperfine interaction, is investigated experimentally and theoretically. The effect is studied using a spin-selective transition in a GaAs double quantum…
Electrically defined semiconductor quantum dots are attractive systems for spin manipulation and quantum information processing. Heavy-holes in both Si and GaAs are promising candidates for all-electrical spin manipulation, owing to the…
We observe the noise spectrum of electron spins in bulk GaAs by Faraday rotation noise spectroscopy. The experimental technique enables the undisturbed measurement of the electron spin dynamics in semiconductors. We measure exemplarily the…
We report on the detection of the intrinsic spin Hall effect in a modulation doped Al-GaAs/GaAs/AlGaAs heterostructure bounded by a self-aligned pn-junction, fabricated by the cleaved edge overgrowth method. Light emission due to the…
We report on our accurate evaluation of spin polarizations of the ground state and particle-hole gaps for partially-filled lowest Landau level, observed in recent experiments on graphene subjected to ultra-high magnetic fields. We find that…
The spin degree of freedom in solids offers opportunities beyond charge-based electronics and is actively investigated for both spintronics and quantum computation. However, the interplay of these spins with their native environment can…
We report on experiments in which a spin-polarized current is injected from a $GaMnAs$ ferromagnetic electrode into a $GaAs$ quantum well through an AlAs barrier. The resulting spin polarization in the GaAs well is detected by measuring how…
Pure spin currents are measured in micron-wide channels of GaAs two-dimensional electron gas (2DEG). Spins are injected and detected using quantum point contacts, which become spin polarized at high magnetic field. High sensitivity to the…