Studies On Optical Modes And Scattering Dynamics In Gaussian-type Parity-time Symmetric Waveguides

It has been developed rapidly since the concept of PT-symmetry comes to people’s minds, especially attracting eyes in the optics. The PT-symmetry means gains and loss is equal in the field of optics and it can be realized by controlling the gains and loss in the waveguide. In this paper, numerical and analytical calculations were used to analyze the pattern and dynamic evolution characteristics of the Gaussian PT-symmetry waveguide. The main contents are as follows:1) Basing on the Schrodinger equation, it can be solved by numerical calculation the soliton modes and the dispersion relation (the relations between propagation constants and the gain/loss coefficients) of the Gaussian PT-symmetry waveguide. The results show that the soliton modes would break with increase of the gain/loss coefficient and the PT-symmetric broken would be restrained because of the nonlinear effect of the waveguides.2) The propagation coefficients of the solitons were obtained through analyzing the coupled mode equations by comparing with the numerical solutions, we conclude that coupled mode equations can only be applied to PT-symmetric waveguides with weak gain/loss effects.3) The dispersion relation of soliton ground state was studied in PT-symmetry waveguide. Unidirectional scattering of the soliton which can be controlled through the balanced gain/loss coefficients was obtained by numerical simulation. Finally, the variational method was used to research the effect of the soliton parameters to unidirectional scattering in PT-symmetric waveguides.