Self-organization in multiple quantum well infrared photodetectors

We investigate the spatio-temporal electric-field distributions in multiple quantum well infrared photodetectors (QWIPs) excited by infrared radiation using ensemble Monte Carlo particle modelling. It is shown that self-organ ized stable periodic electric-field structures can occur in QWIPs excited b y infrared radiation. These electric-field distributions have a period equa l to twice the period of the QWIP structure. The periodic distributions are superimposed by relatively weak spatio-temporal oscillations. The transiti on between two stable periodic structures in response to step-like variatio n of the applied voltage is demonstrated. The periodicity of the electric-f ield structures is conserved after the cessation of illumination for a long time. This time is determined by relatively slow thermoexcitation processe s. The occurrence of the electric-field distributions can pronouncedly affe ct the QWIP steady-state and noise characteristics.