Suppression of Auger Processes in Confined Structures

We explore how the size and shape of the microscopic confinement potential affects the nonradiative Auger decay rate of confined carriers. Calculations conducted in the two-band, effective mass Kane model unambiguously show that smoothing out the confinement potential could reduce the rate by more than 3 orders of magnitude relative to the rate in structures with abruptly terminating boundaries. As the confinement potential width is increased, the calculated rate decreases overall, exhibiting very deep minima at regular widths. Such minima suggest that nanocrystals of "magic sizes" can exist for which nonradiative Auger processes are strongly suppressed.