二维非线性光子晶体点缺陷的双稳态特性
赵年顺;孙剑
【期刊名称】《南昌工程学院学报》 【年(卷),期】2014(000)003
【摘要】采用时域有限差分技术分析了非线性光子晶体点缺陷的双稳态特性,选择一定频率失谐的连续波入射并观察透射现象。分析发现,当连续波功率增加到阈值点时透射率达到最大值。采用大功率脉冲辅助连续波的方式发现点缺陷的透射率一直处于高透射状态,直至连续波功率下降到很低时,透射率才迅速下降。双稳态特性由频率失谐δ、缺陷谐振频率ω0及非线性系数 n2等3个参数决定。采用空间电磁场的摄动理论验证所得结果与数值模拟结果一致。%This paper conducts a research on the bistable characteristics of point defect in two dimensional nonlinear photonic crystals with finite-difference time-domain technique. It analyzes the transmission be-havior of input continuous wave with frequency detuning,and the results show that the maximum transmis-sion is detected when the continuous wave reaches the threshold power. What’s more,the defect can be boosted into high transmission state by superposing continuous wave with a high peak-power pulse,and it won’t decrease rapidly until the continuous wave power is brought down to a very low degree. The fre-quency detuning,the resonant frequency,the nonlinear coefficient n2 are needed to characterize a bistable switch. In addition,the dynamic shift of the cavity modes is derived by using the perturbation theory.