Ultrafast control of light emission from a quantum-well semiconductor microcavity using picosecond strain pulses

A picosecond strain wave packet of subterahertz acoustic phonons is generated in a metal film by optical excitation with a femtosecond laser pulse and injected into a quantum well containing a GaAs-based planar microcavity in the strong-coupling regime. The strain pulse induces a dynamical energy shift of the quantum-well exciton resonance. This results in an ultrafast modulation of the photoluminescence spectrum from the lower polariton branch.