Theoretical investigation of propagation of nonlocal spatial soliton in nematic liquid crystals

In this paper, we investigate the propagation of the nonlocal optical spatial soliton in undoped nematic liquid crystals. On the basis of Schrdinger-type nonlinear equation and reorientation equation, we not only obtained the analytical expression of spatial soliton but also got the expression of breather in the vicinity of the critical power by use of Guassian trial solution. By comparisons of analytical and numerical simulations, we found that our expressions are more precise than those of C.Conti and G.Assanto. Furthermore,we thoroughly compare the nonlocal model in nematic liquid crystals with the linear model suggested by Snyder and Mitchell.