Coherent control of intersubband optical bistability in quantum wells

Abstract

We present a study of the nonlinear intersubband (ISB) response of conduction electrons in a GaAs/Al0.3Ga0.7As quantum well to strong terahertz (THz) radiation, using a density-matrix approach combined with time-dependent density-functional theory. We demonstrate coherent control of ISB optical bistability, using THz control pulses to induce picosecond switching between the bistable states. The switching speed is determined by the ISB relaxation and decoherence times, T1 and T2.