Modelling of carrier transport in non-polar, M- plane III-nitride quantum cascade detectors

In this work, two different designs of mid-infrared (IR) quantum cascade detectors (QCDs) based on non-polar, m-plane III-nitride material system have been presented and the temperature dependent detector characteristics have been investigated. The carrier transport in these QCD structures is modelled using a simplified rate equation approach. The major carrier scattering mechanisms responsible for the intersubband transitions of carriers in non-polar, m-plane III-nitride quantum cascade structures have been identified and included in the rate equation model. The carrier scattering rates are calculated using Fermi's golden rule approximation. The detector performance characteristics have been predicted through the evaluation of current responsivity. It is observed that the resonant tunnel design gives higher responsivity performance compared to the scattering tunnel design whereas the thermal stability of current responsivity of the scattering tunneling design is much better than the resonant tunneling transport design. Both the structures show thermal stability of detection wavelength.