Theory of Auger recombination in a quantum well heterostructure

Abstract We present a calculation of the Auger recombination rate for the CHCC process in a model of a quantum well heterostructure. The calculation differs from the bulk Auger calculations because carriers trapped in the quantum wells reside within sub-bands associated with the different bound states of the wells. The Auger recombination rate is calculated by considering all the possible intra and inter-sub-band carrier transitions. Processes in which the excited electron starts in a bound state of the well but makes a transition to an unbound state are also considered. It has been customary to ignore the bound-unbound transitions but it is shown that they can make a significant contribution to the Auger rate. Simple physical descriptions are used to explain the relative importance of the processes. Numerical results are presented for the Auger rate in 1.3 μm and 1.55 μm InGaAsP/InP quantum well lasers and the major CHCC recombination processes are identified. In these alloys it is found that the quantum well and bulk Auger rates are very similar for the same carrier concentration.