Abstract
Strong anisotropy features (e.g., saddle points) displayed by excited states of (311) valence-band GaAs-AlAs quantum wells are determined through the exact solution of the effective-mass equation including the spin-orbit interaction. Qualitative changes in the topology of the subband energy surfaces occur as the well width is varied. The relevance of the present calculations for the interpretation of recent resonant magnetotunneling experiments on p-type (311)A double-barrier heterostructures is discussed.