Optically detected cyclotron resonance of GaAs quantum wells: Effective-mass measurements and offset effects

Abstract

We have detected cyclotron resonance in a series of undoped GaAs quantum wells by modulating the photoluminescence intensity with far-infrared radiation. The conduction band mass was measured for different quantum well widths, and good agreement with a simple formula based on k · p theory is achieved. An offset was observed in the cyclotron resonance energy, strongly dependent on well width. The interpretation is that monolayer width fluctuations localize the carriers, giving an additional binding energy to the cyclotron resonance transition.