基于光子晶体的THz全光开关响应特性分析

Analysis on the Response Characteristics of THz All-optical Switch Based on Photonic Crystal

选择超短泵浦脉冲激励非线性光子晶体点缺陷,研究了THz全光开关的受激响应特性。研究发现这种具有高品质因子的非线性缺陷在脉冲激励下能迅速响应,特别是当激励脉冲功率密度增大到一定值时,脉冲在高功率密度中的响应延时比泵浦脉冲本身的时域线宽还窄,此外从理论上分析了非线性缺陷模在脉冲激励下发生变化的原因,得出响应速度取决于非线性缺陷模频谱展宽程度的结论。

The ultra-short pump pulse is chosen to excite nonlinear photonic crystal defect and the response characteristics of THz all- optical switch is investigated. The results show that the nonlinear defect with high quality factors can respond rapidly under the excita- tion of pulses, especially when the driving pulse power density increases to a value, the response time of the pulse under high-power densities is even shorter than the duration of the pump pulse. In addition, a theoretical analysis of nonlinear defect spectrum is made to the reasons of changes excited by pulses, coming to a conclusion that the response speed depends on the broadening of nonlinearity de- fect spectrum.