The Weak Light Spatial Soliton In Nematic Liquid Crystal Under External Field

Because the soliton has the same shape,amplitude,and speed in the long-distance propagation,it can realize ultra-long distance and large-capacity optical communication,making it very important in optical communication and optical logic devices.The emergence of optical solitons has played an important role in the field of modern communications,because there is no change of solitons in the entire process of propagation,which ensures the accuracy of information.At the same time,it also has many advantages such as large capacity,low bit error rate,and strong anti-interference ability.Spatial solitons have always been the research frontier of nonlinear optics,so it is especially important to find a suitable medium to study spatial optical solitons.In the past studies,nematic liquid crystals have been found in this medium.The large optical nonlinearities it has are just the favorable media for exploring optical solitons.From the nonlinear equations describing the propagation of light waves in a nonlinear medium,the propagation equations of the incident light are deduced when the nematic liquid crystal responds to the light intensity in low-light conditions.Based on the existing boundary condition of optical solitons,the bright and dark spatial soliton solutions of the nematic liquid crystals based on the light intensity response,the optical intensity expressions of the optical solitons and the width expression of the optical soliton are deduced.The normalized light field distribution,normalized light intensity distribution,and width of the optical soliton are simulated.At the same time,the factors affecting the optical field,light intensity,and width of solitons are analyzed.It is found that the nonlinear coefficient of the liquid crystal,the amplitude of the incident light wave,and the change in the refractive index of the nematic liquid crystal all affect the light field,the light intensity,and the width of the spatial soliton.Starting from the beam propagation equation in the nonlinear medium,the spatial soliton under the light field response in the nematic liquid crystal is deduced.Using the method of numerical integration,the solutions of bright and dark spatial solitons are deduced.And the optical intensity and width of optical solitons are deduced too.At the same time,the normalized light field,the light intensity,and the width of the soliton of the soliton are simulated.The factors that affect the optical soliton light field,light intensity,and width are analyzed.Combining the elasticity theory of liquid crystals with the electronically controlled deflection characteristics of liquid crystals,the propagation equation of incident light waves in nematic liquid crystals is generalized.The propagation of the light beam in the nematic liquid crystal and the propagation of the light beam in the nematic liquid crystal when there is no refractive index change are simulated.By comparison,it is found that spatial optical solitons can be formed only when the refractive index of the nematic liquid crystals changes.