Simulation of Heat Propagation Processes in the Five-Layer Detection Pixel with FeSb2 Sensor After Simultaneous Absorption of Several Photons

The results of modelling of heat propagation processes in the five-layer detection pixel of a thermoelectric single-photon detector after absorption of several photons are presented. We have considered the absorption of photons in the detection pixel with a surface area of 10 × 10 μm 2 and various thicknesses of the antireflection layer (SiO 2 ), absorber (W), thermoelectric sensor (FeSb 2 ), heat sink (W), and substrate (Al 2 O 3 ). To simulate of heat transfer processes the technique based on the equation of heat propagation from a limited volume is used. The cases of simultaneous absorption of several photons at a length of 1 μm of the absorber surface are investigated. It is shown that it is possible to determine the number of absorbed photons up to 8.