Exchange interaction effects in quantum well infrared detectors and absorbers

Abstract
Infrared excitation energies between the ground-state subband and the first excited-state subband in quantum wells are analyzed including the effect of exchange interactions on the ground-state subband. Analytic and numerical calculations relevant to infrared absorption and infrared detection are performed. Previous work on exchange interaction effects in narrow wells is extended to deal with well widths which can provide absorption peaks and photocurrent peaks throughout the long-wavelength infrared and very-long-wavelength infrared regime. Exchange effects are shown to be substantial.