Nonlinear response of low-background extrinsic silicon detectors. 1: A phenomenological model

Extrinsic photoconductive silicon detectors operated in the infrared at low-background flux and high bias voltage respond nonlinearly to strongly modulated illumination. They can exhibit a dc nonlinear response even at low bias. We present a simple mathematical prescription for computing the output corresponding to a given input signal. This phenomenological model predicts results in reasonable agreement with measured response data for square wave input modulation.