角度可调谐硅基氮化镓导模共振滤波器

The Angle Adjustable Si-Based GaN Guided-Mode Resonance Filters

根据严格耦合波理论和等效介质理论,研究了工作于1 300-1 400nm波段的基于硅基GaN（氮化镓）亚波长光栅的导模共振滤波器。分别讨论了在强调制光栅和弱调制光栅作用下,滤波器反射谱对光栅周期和入射角度的敏感性。利用其对入射角度的敏感性,结合仿真分析设计了一种利用微机电系统静电梳齿驱动器改变光栅角度从而控制不同的共振波长输出的角度可调谐硅基GaN导模共振滤波器。仿真分析结果表明,在强调制情况下,角度可调谐范围为0.5-5.7°,波长可调谐范围为1 319-1 352nm,FWHM（半高全宽）〈2.2nm。

Based on the rigorous coupled wave theory and equivalent medium theory,a Si-based GaN guided-mode resonance fil-ter with the operation wavelength ranging from 1 300 to 1 400 nm was studied.The effects of the grating period and incident angle on the reflective spectra of the filter were analyzed under strong modulation and weak modulation condition.Also,the sensitivity of the reflection spectrum under different grating period and incident angle was studied.According to the sensitivity of the reflection spectrum to the incident angle of the grating period in the strong modulation condition,an angle adj ustable Si-based GaN guided-mode resonance filter was proposed.The incident angle of the grating is tuned by a MEMS electrostatic comb drive to control the output of the different resonance wavelength.The simulation results demonstrate that the incident angle could be tuned from 0.5 to 5.7 °and the corresponding wavelength could be tuned from 1 319 to 1 352 nm with the FWHM less than 2.2 nm.