Space charge effects in carrier escape from single quantum well structures

Recently published data on the variation with applied bias and temperature of steady-state photoluminescence and photoconductivity from a series of Ga As/AlGaAs single quantum well p-i-n structures are subjected to detailed th eoretical analysis, using phenomenological variables introduced in connecti on with these results. The data are interpreted as revealing the presence i n the well of a space charge, which causes band bending and hence indirectl y modifies carrier escape lifetimes. It is shown that the thermionic escape of holes can affect the electron tunneling escape lifetime so that the lat ter displays a thermal activation energy which is quantitatively similar to the hole well depth. (C) 1999 American Institute of Physics. [S0021- 8979( 99)09920-X].