EFFECT OF ELECTRON AND PHONON ANISOTROPY ON THE PHONON-DRAG THERMOPOWER OF A CLASSICAL 2-DIMENSIONAL ELECTRON-GAS IN A MAGNETIC-FIELD

The standard theory of the phonon-drag thermopower tensor (S) over cap for a classical two-dimensional electron gas in a perpendicular magne tic field B describes fairly well the longitudinal tensor element S-yx (g). However, the transverse tensor element S-yx(g) is only similar to 0.5% of what is measured in a GaAs/AlGaAs quantum well. This large er ror fan be removed when B < 3 T by allowing for the simultaneous prese nce of electron and phonon anisotropy. The restriction on B is introdu ced only to gain physical insight. Similar results ars expected when S -yx(g) becomes nonlinear in B and in the Landau quantization regime. [ S0031-9007(98)05402-7].