Coherent Terahertz Radiation Emission by Cavity Polaritons in a GaAs/AlGaAs Microcavity
01 March 2000
We observe coherent far-infrared electromagnetic radiation emitted from a gamma-wide, GaAs/AlGaAs microcavity (MC). The radiation is emitted under resonant, pulsed photoexcitation of the two cavity polariton modes, at T=4.7K.
The electromagnetic radiation frequency is equal to the vacuum Rabi splitting frequency and, thus, the emission is due to quantum oscillations between the MC and the exciton modes that induce an electric dipole oscillating at the Rabi frequency. These experiments demonstrate the existence of an inter-polariton dipole interaction under no applied external electric field.