Quantum well infrared photodetectors: Monte Carlo simulations of transport

This letter describes some Monte Carlo simulations of electron transport in quantum well infrared photodetectors designed to operate in the 10 μm wavelength range. These GaAs/AlGaAs superlattice photodetectors absorb radiation between a bound state in the wells and the continuum of states above the wells. We have studied the collection efficiency of the photoexcited electrons at 70 K as a function of bias across the device, as well as the response time. It is concluded that the quantum mechanical well capture transition rate through interaction with LO phonons, between the extended states in the continuum and the bound state, has to be considered for agreement with the experimental results.