三能级冷原子介质中多个光孤子的相互作用

Interaction of multi-optical solitions in the three-level gaseous media

冷原子介质中的光孤子在电磁感应透明(EIT)的作用下表现出很多奇异的特性,对描述这些特性的理论模型的研究在光信号处理和传输方面具有重要的意义.描述三能级冷原子EIT介质中空间孤立子演化的二维饱和非线性薛定谔方程被转化成辛结构的Hamilton系统,利用辛几何算法离散Hamilton系统得到了相应离散的辛格式,并且利用辛格式数值模拟了三能级冷原子EIT介质中在相同振辐不同相位的两个、四个光孤子的相互作用行为.数值实验结果表明:冷原子介质中多个光孤子的相互作用行为不但与入射高斯光束的相位有关,还和入射高斯光柬的方向有关.入射的高斯光束能在冷原子介质中形成稳定的孤立子.

Optical solitons in gaseous atomic media display many striking features under electromagnetically induced transparency（EIT）. Study of theoretical model,which describes these features of optical solitons,has important meaning in optical informational process and propagation.Two-dimensional saturated nonlinear Schrodinger equation,which describes the spatial soliton evolution in the threelevel gaseous atomic EIT media,is transformed into the Hamilton system with the symplectic structure.The Hamilton system is discretizated by the symplectic method.The corresponding symplectic scheme is obtained.Evolution behaviors of two and four spatial solitons with the same amplitude in a three-level,gaseous atomic EIT media are simulated by the symplectic scheme.Numerical results further show that the phase difference and the direction of the entering gauss beams have an obvious effect on the interaction of multi-solitons.The entering Gauss beam can form the stable optical solitons in a gaseous atomic media.