Magneto-optical absorption in an overfilled parabolic quantum well. I. Tilted field

We study the far-infrared optical-absorption spectrum and collective excitations of electrons confined in an imperfect parabolic quantum well in a magnetic field tilted with respect to the growth axis. Using a self-consistent-field approach both with and without a local exchange-correlation potential, we calculate spectra for an ‘‘overfilled’’ well with abrupt boundaries. We choose well parameters to match a real experimental sample, and investigate the effects of well asymmetry and finite temperature on the optical spectrum. We compare our calculations to experiment and find excellent agreement over a wide range of magnetic-field strengths. We also study the effects of overfilling on the low-lying collective excitations, and find that in the sample considered, nonparabolicities are strong enough to shift the energies of the excitations substantially from their ideal-well values.