Effect of an external resonator on the stimulated emission of a semiconductor microcavity with embedded quantum wells

Abstract

The effect of an external resonator on the emission of a GaAs microcavity with embedded quantum wells is investigated experimentally and theoretically. It was shown that the external resonator controls the process of the stimulated emission of the microcavity leading to the threshold-like appearance of closely separated modes in a spectrum and to oscillations in the temporal dynamics of the emission. Investigation of the spatial coherence with a temporal resolution shows a complex phase dynamics related to the interplay between the lasing modes and reveals a strong spatial inhomogeneity of a phase within each mode. [7] and the relation between polariton and photon BEC and a conventional laser is actively discussed [8][9][10][11][12]. It should be noted, however, that true BEC in a pure two-dimensional system, such as an ideal planar MC, is impossible according to the HohenbergMermin-Wagner theorem [13]. Therefore, polariton condensation observed in the experiments results from the finite size of the system, which is limited either by the excitation spot or by a lateral confining potential for polaritons. This potential is formed by an MC lateral disorder [5,14,15], applied stress [16], or artificially by producing MC micropillars [17,18]. It provides a favorable condition for the polariton condensation [16] and leads to a significant modification of