Excitation and relaxation of non-equilibrium states in mesocopic semiconductor rings

Andrey Moskalenko

Max-Planck Institut fuer Mikrostrukturphysik

We study non-equilibrium states in mesoscopic semiconductor rings created by excitation with picosecond half-cycle pulses of electromagnetic radiation. For the case of low temperature the dynamics of the pulse-induced electric dipole moment is calculated both numerically and analytically. The oscillating dipole moment leads to the emission of radiation with frequency in the range 10-100 GHz depending on the properties of the ring. By specially designing a sequence of half-cycle pulses a macroscopic current can be generated in the ring and the polarization properties of the radiation emitted from the ring can be controlled. We investigate relaxation processes leading to the decay of the non-equilibrium states and therefore to the decay of the dipole moment and current and show that the observation of the phase-coherent properties is feasible. description: My present research interests are: Transport and optical phenomena in semiconductor nanostructures. Quantum dynamics in nanostructures. Excitation and control of qunantum systems by half-cycle pulses. Excitation and deexcitation of erbium ions in silicon dioxide with silicon nanocrystals.