矩孔光子晶体可见光谱段窄带偏振陷波研究

Narrow-Band Polarization Notch Filteringof Visible Light Spectra Based on Photonic Crystal with Periodic Rectangular Holes

提出一种可见光谱段内窄带偏振陷波滤波的矩孔光子晶体结构。通过建立矩孔光子晶体模型,将矩孔光子晶体结构等效为介质层-光栅层-介质层周期结构,利用Rugate滤波理论对矩孔光子晶体结构进行分析,结合等效介质理论(EMT)和传输矩阵方法(TMM)对结构模型的入射光s偏振、p偏振的透过率进行仿真。另外讨论了矩孔光子晶体纵向周期数m、光栅层填充比f、厚度d等参数对偏振陷波的中心波长、带宽以及截止带透过率的影响。针对417,497,582,685nm中心波长,设计带宽为10nm的p偏振窄带陷波结构,并用时域有限差分方法(FDTD)进行仿真验证,结果表明,矩孔阵列结构可以实现可见光谱段内窄带偏振陷波滤波。

A novel photonic crystal (PC) structure with periodic rectangular holes is proposed to realize the narrow-band polarization notch filtering of visible lights. This PC structure is equivalent to a periodic structure with a dielectric-grating-dielectric layer in the PC structure model. The PC structure is first analyzed by the Rugate filtering theory and then the equivalent medium theory (EMT) and the transmission matrix method (TMM) are combined to simulate the transmittances of lights with s and p polarizations. The effects of the parameters, such as longitudinal period number m, filling ratio of grating layers f and thickness d of this PC structure, on the central wavelength, band width and transmittance in the cut-off zone for polarization notch filtering are also discussed. As for the central wavelengths of 417, 497, 582, 685 nm, a p-polarization notch filtering structure with a band width of 10 nm is designed, which is tested by the simulation with the finite difference time domain (FDTD) method. The results show that the PC structure with periodic rectangular holes can be used to realize the narrow-band polarization notch filtering of visible lights.