FUNDAMENTAL RELATION BETWEEN ELECTRICAL AND THERMOELECTRIC TRANSPORT-COEFFICIENTS IN THE QUANTUM HALL REGIME

The two components S-xx and S-yx of the phonon-drag thermoelectric pow er in two-dimensional electron gases (2DEGs) are found to be related b y S-yx = alpha B(dS(xx)/dB) in the integer and fractional quantum Hall regime. A similar relation exists for electrical resistivity, rho(xx) = alpha B(d rho(xy)/dB), and we show that experimentally the constant alpha is the same in both cases indicating the universal character of such relations for transport in 2DEGs. These results link the behavio r of S-yx, which hitherto has not been understood, to that of S-xx and thus opens a new way of explaining this quantity.