论文部分内容阅读
利用对入射光源偏振性不敏感的二维金光栅结构来增强AlGaN/GaN量子阱中红外光电探测器的垂直光耦合。采用有限元法(FEM)计算了探测器结构中的电场分布和能量流动,发现采用二维金光栅时量子阱区有效电场强度比采用Si_3N_4光栅时高出2个数量级,这主要源于金光栅与AlGaN界面处激发形成的表面等离激元(SPP),对光能流动方向、光场振动方向产生了强烈的改变。无论光源的偏振性如何,当垂直入射电磁波波长为4.7μm,电场强度E为1 V/m时,量子阱区的有效|E_z|~2达到了0.7(V/m)~2,为实现AlGaN/GaN量子阱中红外光电探测器焦平面阵列提出了一种解决方案。
The vertical optical coupling of infrared photodetectors in AlGaN / GaN quantum wells is enhanced by using a two-dimensional gold grating structure that is insensitive to the polarization of the incident light source. Finite element method (FEM) is used to calculate the electric field distribution and energy flow in the detector structure. It is found that the effective electric field intensity in the quantum well region when using two-dimensional gold grating is two orders of magnitude higher than that of Si_3N_4 grating, Surface plasmon polaritons (SPPs) excited at the AlGaN interface strongly change the direction of light energy and the vibration direction of the light field. Regardless of the polarization of the light source, the effective | E_z | ~ 2 of the quantum well reaches 0.7 (V / m) ~ 2 when the wavelength of vertical incident electromagnetic wave is 4.7μm and the electric field intensity E is 1V / m. / GaN quantum well mid-infrared photodetector focal plane array presents a solution.