基于一维间距调制型光子晶格的光传输现象

摘要

采用数值模拟方法研究了高斯光束在四种间距调制型光子晶格中的传输规律。研究发现：在具有两个正双曲正割势垒和矩形势垒的晶格阵列中，光波在势垒处发生明显的衍射现象，而在势阱处发生强烈的局域现象；在具有两个负双曲正割势垒和负矩形势垒的晶格阵列中，光波可在势垒处发生无反射传输或在势垒中发生局域现象；而在势阱中振荡衰减传输。研究还发现在低功率情况下，负势垒支持的线性模式间可以发生振荡耦合；高功率非线性情况下，光波将发生局域现象。研究结果为利用光子晶格调节和控制光波传输，实现全光开关提供了新的思路和方法。%We numerically study the propagations of Gaussian beams in four types of separation modulated photonic lattices. The results shows that the potential wells between double positive hyperbolic secant and rectangular potential barriers and between the potential barriers in the forms of double negative hyperbolic secant and rectangular functions can both support localized linear modes. Moreover, the coupling effects between two linear modes in the potential barriers can be used to realize all-optical switch. Furthermore, the nonlinear localization can also be observed in high power. Our results supply new ideas for all optical switch, light controlling and manipulation in photonic lattices.