Numerical optimization of bolometric infrared detectors including optical loading, amplifier noise, and electrical nonlinearities

We present numerical methods for the optimization of bolometric infrared detectors which use current-biased semiconducting thermistors. We extend the analysis of Griffin and Holland to explicitly include both the electric field dependence of the thermistor resistance and amplifier noise. These methods allow the user to design and evaluate an optimized bolometer once such parameters as the optical loading, the heat sink temperature, and the materials for the thermal link and the thermistor have been chosen. Measured parameters which describe the electrical nonlinearities in neutron transmutation doped germanium are presented. The consequences for bolometer optimization of including these effects are illustrated. This program will be made available at the web site http://physics7.berkeley.edulbolometer.html.