We present the results of a new model for the simulation of quantum well infrared photodetectors (QWIPs) both in dark conditions and under illumination. This model takes into account the elementary mechanisms involved in the detection process (injection at the contacts, balance between capture and emission in each well) in a self-consistent way. The main feature emerging from the model is the redistribution of the electric field along the structure in order to maintain current conservation. The calculated dark current, electrical noise, responsivity, and detectivity of different QWIP structures are compared with experimental measurements and the agreement is found to be fairly good. This model may be considered as a step toward more powerful simulation tools for QWIPs.

No abstract

We have theoretically investigated the capture of electrons into a quantum well by LO phonon scattering. The calculation was performed for a single, undoped GaAs/AlxGa1−xAs quantum well under applied electric bias. We have derived an expression for the time constant associated with the exchange of electrons between the fundamental ground state and the continuum states. The results are found to be in fairly good agreement with impedance spectroscopy measurements.

No abstract

No abstract