We investigate the spontaneous formation of quantized vortices in microcavity polariton high density phases. Condensates formed in the optical parametric oscillator excitation scheme reveal single vortices in the case of a ring-shaped optical potential or in the presence of natural photonic disorder. We further investigate the dynamics of vortex formation for resonantly injected polaritons and observe the formation of vortex-antivortex pairs, but no single vortices. The observed effects are explained by the interplay between breaking of $y\mapsto -y$ reflection symmetry in the system and conservation of optical angular momentum.

• Received 13 November 2012

DOI:https://doi.org/10.1103/PhysRevB.87.081309