Quantum correlation induced intraband coherences in a quantum-well microcavity

Summary form only given. We demonstrate that quantum correlations between the cavity field and the carrier density in an InGaAs quantum-well (QW) microcavity can be observed in a novel pump-probe experiment. In our investigations, the lower normal mode of a microcavity is excited with a pair of identical phase-locked pump pulses near normal incidence. The transient reflectivity of a weak probe pulse tuned to the upper normal mode is measured. We will show that long-lived oscillations are observed, which originate in the pump-induced quantum correlations, and that the phase and amplitude of the coherences can be controlled via the relative phase of the pump pulses.