Within the framework of a simple envelope function and effective mass appro
ximation, by including the spatial variation of effective mass and nonparab
olicity effects, we have investigated the energy spectrum and intersubband
optical absorption in a quantum well with additional thin and higher (delta
-like) cladding barriers on either side of the well. The dependence of the
absorption coefficient on the structure parameters, doping level, photon en
ergy and temperature has been investigated. The absorption coefficient and
spectrum strongly depend on the cladding barrier tunnel transparency. The p
eak absorption wavelength is shifted towards the high energies as the barri
er transparency decreases. The temperature shift of the absorption peak is
very small. The results are compared with experiments of Schneider et al. [
7, 8] taking into account the broadening induced by well width fluctuations
. (C) 1999 Academic Press.