Gap solitons and symmetry breaking in parity-time symmetric microring   CROWs
  The propagation properties of optical fields in linear and nonlinear parity-time symmetric microring coupled resonator optical waveguides are studied. The effects described include the existence of symmetry breaking thresholds, the propagation of gap solitons in nonlinear transmission lines and the existence of quasi stable propagation regimes outside the broken symmetry regions. 
Pedro Chamorro-Posada
physics.optics nlin.PS