Related papers: Goldstone mode stochastization in quantum Hall fer…
It is shown that the low-energy spectrum of a ferromagnetic quantum Hall effect liquid in a system with a multi-domain structure generated by an inhomogeneous bare Zeeman splitting $\epsilon_{Z}$ is formed by excitations localized at the…
Access to collective excitations lies at the heart of our understanding of quantum many-body systems. We study the Higgs and Goldstone modes in a supersolid quantum gas that is created by coupling a Bose-Einstein condensate symmetrically to…
In two-dimensional electron systems confined to GaAs quantum wells, as a function of either tilting the sample in magnetic field or increasing density, we observe multiple transitions of the fractional quantum Hall states (FQHSs) near…
We develop an effective low energy theory of the Quantum Hall (QH) Smectic or stripe phase of a two-dimensional electron gas in a large magnetic field in terms of its Goldstone modes and of the charge fluctuations on each stripe. This…
The spin relaxation time due to the electron-acoustic phonon scattering in GaAs quantum dots is studied after the exact diagonalization of the electron Hamiltonian with the spin-orbit coupling. Different effects such as the magnetic field,…
Spontaneous symmetry breaking is ubiquitous in physics. Its spectroscopic signature consists in the softening of a specific mode upon approaching the transition from the high symmetry side and its subsequent splitting into a zero-frequency…
The D'yakonov-Perel' spin relaxation mechanism in n-doped GaAs/AlGaAs quantum wells (QWs) has been studied both theoretically and experimentally. The temperature dependence of the spin relaxation time has been calculated for arbitrary…
We have investigated the spin dynamics of a high-mobility two-dimensional electron system (2DES) in a GaAs--Al$_{0.3}$Ga$_{0.7}$As single quantum well by time-resolved Faraday rotation (TRFR) in dependence on the initial degree of spin…
The spin fluctuations of electron and hole doped self-assembled quantum dot ensembles are measured optically in the low-intensity limit of a probe laser in absence and presence of longitudinal or transverse static magnetic fields. The…
The synchronized magnetization dynamics in ferromagnets on a nonmagnetic heavy metal caused by the spin Hall effect is investigated theoretically. The direct and inverse spin Hall effects near the ferromagnetic/nonmagnetic interface…
Separate spin evolution quantum hydrodynamics is generalized to include the Coulomb exchange interaction. The Coulomb exchange interaction is considered as the interaction between the spin-down electrons being in the quantum states occupied…
We study quantum Hall ferromagnets in the presence of a random electrostatic impurity potential. Describing these systems with a classical non-linear sigma model and using analytical estimates supported by results from numerical…
The periodical modulation of circularly polarized light with a frequency close to the electron spin resonance frequency induces a sharp change of the single electron spin orientation. Hyperfine interaction provides a feedback, thus fixing…
We study the quantum phase transition occurring in an infinite homogeneous system of spin 1/2 fermions in a non-relativistic context. As an example we consider neutrons interacting through a simple spin-spin Heisenberg force. The two…
Goldstone modes in the amorphous solid state, resulting from the spontaneous breaking of translational symmetry due to random localisation of particles, are discussed. Starting from a microscopic model with quenched disorder, the broken…
We theoretically investigate a two-dimensional harmonically-trapped gas of identical atoms with Rashba spin-orbit coupling and no interatomic interactions. In analogy with the spin Hall effect in uniform space, the gas exhibits a spin Hall…
We investigate theoretically the coherent longitudinal and transversal spin relaxation of photoexcited electrons in quantum wells in quantized magnetic fields. We find the relaxation time for typical quantum well parameters between 100 and…
We investigate theoretically the spin states in InAs/AlSb/GaSb broken-gap quantum wells by solving the Kane model and the Poisson equation self-consistently. The spin states in InAs/AlSb/GaSb quantum wells are quite different from those…
We have studied the physical processes responsible for the spin -flip in GaAs quantum dots. We have calculated the rates for different mechanisms which are related to spin-orbit coupling and cause a spin-flip during the inelastic relaxation…
We use temporally resolved intensity cross-correlation measurements to identify the biexciton-exciton radiative cascades in a negatively charged QD. The polarization sensitive correlation measurements show unambiguously that the excited two…