Bright Solitons In The Self-defocus Medium With Cubic-quintic Nonlinearities

"soliton", which has wave-particle duality, is widely concerned by people because of its special properties that can maintain the stability of the shape during the transmission process. Moreover, the soliton transmission conform to the demand of modern communication of high capacity, low loss and strong anti-interference, the mode of all-optical nonlinear optical soliton communication is most likely to become one of the future communication options. Due to the special nonlinear properties and applications in the field of communication, the soliton has become one of the hottest research topics in the field of nonlinear.The propagation properties of soliton in various nonlinear materials and the characteristics of these materials theoretically are studied. In this paper, we introduce the basic concepts of soliton and the main theoretical models that support soliton transmission, and investigate the one/two-dimension nonlinear Schr?dinger equation with cubic-quintic nonlinearities from the symmetrical self-defocus medium. The pulse soliton solution to this model is obtained in the case that the cubic-quintic nonlinear strengths are the exponential function of the transverse coordinate(s) and the stability of the solution is analyzed by using the split step Fourier method. It was numerically found that the stability of soliton depends on propagation constant. Soliton propagation distance increases with propagation constant.