Transmutation from Skyrmions to Half-Solitons Driven by the Nonlinear   Optical Spin-Hall Effect
  We show that the polarization domains generated in the linear optical spin-Hall effect by the analog of spin-orbit interaction for exciton-polaritons are associated with the formation of a Skyrmion lattice. In the non-linear regime, the spin anisotropy of the polariton-polariton interactions results in a spatial compression of the spin domains and in an abrupt transformation of the Skyrmions into half-solitons, associated with both the focalization of the spin currents and the emergence of a strongly anisotropic emission pattern. 
H. Flayac, D. D. Solnyshkov, I. A. Shelykh, and G. Malpuech
cond-mat.mes-hall cond-mat.quant-gas