Fig. 1. （a）The 3D schematic diagram and（b）the center cross-section of a pixel with infrared radiation at the normal angle as the simulated and experimental multilayer coatings for T2SL infrared photodetector model in this study

Fig. 2. The response spectra of single-unit device under front illumination，（a）experimental and（b）simulation spectra assuming the refractive indices of InAsSb are 1.5，2 and 2.5，respectively.（c）the optical field distribution when the refractive index of InAsSb is 2 and the response wavelengths are 11.5 μm and 8.7 μm，respectively

Fig. 3. [in Chinese]

Fig. 4. （a）The simulation and experimental response spectra of T2SL FPAs，（b）the comparison and enhancement of the FPAs’ response without and with multi-coatings