Polaron Problem in Quantum Wells

Polaron Effects on the Stark Shift of a Bound Polaron in Finite Quantum Wells

We performed electron spin and nuclear magnetic resonance and inelastic neutron scattering measurements of a single crystal of lightly hole-doped La1−xSrxCoO3, x ∼ 0.002 in order to establish the origin of a surprisingly strong magnetization due to a very small Sr doping. The data provide experimental evidence for the creation at low temperatures of extended spin clusters with a large spin mult...

Lattice exciton-polaron problem by quantum Monte Carlo simulations

Exciton-polaron formation in one-dimensional lattice models with shortor long-range carrier-phonon interaction is studied by quantum Monte Carlo simulations. Depending on the relative sign of electron and hole-phonon coupling, the exciton-polaron size increases or decreases with increasing interaction strength. Quantum phonon fluctuations determine the excitonpolaron size and yield translation-...

Quantum control of polaron states in semiconductor quantum dots

We study phonon-assisted dephasing in optically excited semiconductor quantum dots within the frameworks of the independent Boson model and optimal control. Using a realistic description for the quantum dot states and the phonon coupling, we demonstrate that such dephasing has a drastic impact on the coherent optical response. We employ optimal control theory to search for control strategies th...

Magnetoresistance in Coupled Quantum Wells

The in-plane magnetic field suppresses the quantum coupling between electrons in a double quantum well structure. The microscopical theory of this effect is developed and confirmed experimentally. We have shown that the decrease of the " resistance resonance " peak is sensitive to the mutual orientation of the current and the in-plane magnetic field. The characteristic field required for the su...

Numerical solution of the Holstein polaron problem