Polariton parametric oscillation in a single micropillar cavity

We demonstrate parametric oscillation of discrete polariton states in a single squared GaAs/GaAlAs micropillar cavity. Resonantly exciting a selected polariton mode with a continuous wave pump laser, parametric oscillation is evidenced on the two neighbored modes (signal and idler). Abrupt switch-off of the device is observed under high excitation. We present comprehensive results concerning the power-dependence of the energy and linewidth of the emission resonances as well as their far-field patterns. Quantum Monte Carlo calculations give a quantitative understanding of the physics of this micro-optical parametric oscillator involving fully confined discrete polariton modes.