Spatial Solitons in Media with Delayed-Response Optical Nonlinearities
  Near-soliton scanning light-beam propagation in media with both delayed-response Kerr-type and thermal nonlinearities is analyzed. The delayed-response part of the Kerr nonlinearity is shown to be competitive as compared to the thermal nonlinearity, and relevant contributions to a distortion of the soliton form and phase can be mutually compensated. This quasi-soliton beam propagation regime keeps properties of the incli- ned self-trapped channel. 
Evgeny V.Doktorov and Rafael A.Vlasov (Institute of Physics, 220072   Minsk, Belarus)