Controllable half-vortex lattices in an incoherently pumped polariton   condensate
  We show how the transition between synchronized and desynchronized states of a spinor polariton condensate can be used to drive a transition between stationary vortex lattices and half-vortex lattices. This provides a way to control polariton spin textures by a combination of pump spot profile and applied magnetic fields. To do this, we extend the model of non-equilibrium spinor condensates to include relaxation, and study how this affects the desynchronization transition. We discuss how the pattern formation can be explained by behavior of the homogeneous system. 
Jonathan Keeling and Natalia G. Berloff
cond-mat.quant-gas