Non‐linear dynamical effects in semiconductor microcavities

Abstract

An investigation of the parametric amplification and its coherent control in a semiconductor microcavity is presented. The time and angle resolved pump and probe experiments show that several picoseconds after pumping the polaritons are still coherent and parametric scattering is still going on. The experimental data concerning the time integrated measurements are in qualitative agreement with the numerical data obtained from a relatively simple theoretical model based on three polarisation components, pump, probe, and idler. As for the dynamics of parametric amplification in real time, the measurements reveal that often stimulation is considerably delayed with respect to the arrival of pump and probe. Even though the observed dynamics is complex, our simple theoretical model permits to reproduce several of the experimental features. (c) 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Fifteen Years of Microcavity Polaritons

“…It has a sharp resonant character and hence is extremely fast, allowing switching times below 1 ps even at liquid nitrogen temperature in II-VI samples. In samples with small inhomogenous broadening, it persists up to high temperature, thanks to the polariton robustness to loss mechanisms, and it can be coherently controlled [81] (see also the contributions by Baumberg et al [13] and by Staehli et al [139] to the present volume). When GaN-based polariton samples will finally be available [22,147] (see also the contribution by Carlin et al [24] to the present volume), the amplification should persist at room temperature, thus opening the way to possible applications as fast optical switches or amplifiers.…”

“…Ideally, nonlinear effects in a QW become important when the excitons approach the saturation density [133]. Recently, however, more subtle nonlinear effects such as the polariton parametric scattering [33,35,131,141] have been observed in the limit of the lowest densities accessible in an optical experiment (see also the contributions by Staehli et al [139], by Baumberg et al [13], and by W. Langbein [85] to the present volume). The second important difference between atom-cavity normal-mode coupling and bulk polaritons is the way the single-mode selection is performed.…”