Modelling of electronic transport in Quantum Well Infrared Photodetectors

Our interest is to model the electronic transport in Quantum Well Infrared Photodetectors (QWIPs). Standard modelling was based on self-consistent calculation of the non-uniform electric field with empirical description of the electron capture (Thibaudeau et al., 1996 [17]). Realistic empirical parameters had to be extracted from experiment, consequently purely numerical studies were not possible. Moreover, this approach allowed only a qualitative description of transport phenomena. In order to get rid of adjustable parameters, we have changed for a modelling based on the microscopic description of the transport (Jovanović et al., 2004 [11]). We have applied this modelling to the design of a variety of QWIPs. For example, excellent agreement with experimental dark current–voltage curves for different sizes of the barriers is demonstrated on a 8 μm detector over more than 6 orders of magnitude. The behaviour with respect to temperature on a wide range (30–200 K) is also well reproduced on this device as well as on a 17 μm detector. Those promising results confirm that this approach can give not only a good quantitative agreement but can also be a useful predictive tool.