点缺陷、线缺陷耦合THz波全光开关特性研究

采用基于时域有限差分技术的数值模拟方法，研究了点缺陷和线缺陷复合的光子晶体结构，分析了在不同功率强度下入射光的透射行为。分析结果发现，当入射光频率与缺陷模谐振频率相等时，点缺陷束缚入射光，入射光透射率表现为“断”的状态；当入射光频率与缺陷模中心频率不相等时，入射光透射率表现为“通”的状态。而改变入射光功率强度会使缺陷模的位置发生移动，从而实现了THz波透射率调制的功能。该结论为设计THz波全光开关提供了重要依据。

Characteristics of THz Wave All-optical Switch Formed by Point Defects and Line Defects Coupling

Numerical simulations based on the finite difference time domain technique was employed to investigate the photonic crystal structure formed by point and line defects coupling. And the incident light transmission behaviors at different power were analyzed. Results showed that when the frequency of incident light was consistent with the de- fect mode resonant frequency, the incident light will be bound by the point defect, and transmittance was of “off” state. When the frequency of incident light was inconsistent with the defect mode resonant frequency, the state was “on”. The defect mode will be shifted when the power intensity of the incident light changes, so as to realize the modulation of THz wave transmittance. The conclusion provides an important reference for the design of THz wave optical switch.