Evidence for quantum well asymmetry in optical absorption

Some previously unexplained features of the experimentally determined optical spectra of GaAs/Ga1−xAlxAs heterostructures are theoretically explained in terms of unintentionally introduced asymmetries in the shape of semiconductor quantum wells which break the usual optical selection rules. Various mechanisms that may be responsible for well asymmetries are suggested. Their measurement may be a useful characterization tool in quantum well fabrication.