Stable Switching among High-Order Modes in Polariton Condensates
  We report multistate optical switching among high-order bouncing-ball modes ("ripples") and whispering-gallerying modes ("petals") of exciton-polariton condensates in a laser-generated annular trap. By tailoring the diameter and power of the annular trap, the polariton condensate can be switched among different trapped modes, accompanied by redistribution of spatial densities and superlinear increase in the emission intensities, implying that polariton condensates in this geometry could be exploited for a multistate switch. A model based on non-Hermitian modes of the generalized Gross-Pitaevskii equation reveals that this mode switching arises from competition between pump-induced gain and in-plane polariton loss. The parameters for reproducible switching among trapped modes have been measured experimentally, giving us a phase diagram for mode switching. Taken together, the experimental result and theoretical modeling advances our fundamental understanding of the spontaneous emergence of coherence and move us toward its practical exploitation. 
Yongbao Sun, Yoseob Yoon, Saeed Khan, Li Ge, Loren N. Pfeiffer, Ken   West, Hakan E. Tureci, David W. Snoke, and Keith A. Nelson
cond-mat.mes-hall quant-ph