Photomodulated absorption spectroscopy on AlGaAs-GaAs heterostructures

Abstract
Optical transitions in quantum-well heterostructures are very well revealed by photomodulated absorption spectroscopy. With respect to nonmodulated absorption spectroscopy, a strong increase in both room-temperature resolution and signal-to-noise ratio is observed. This new technique is most attractive for the investigation of multilayers grown on transparent substrates. The evolution of the spectral lineshapes of bulk and excitonic transitions as a function of temperature is shown.