QUANTUM HALL-EFFECT AT FINITE TEMPERATURES

We point out that the universality and precision of the Hall plateaus of H-1 in the quantum Hall effect (QHE) can be understood if the conducting component of the two-dimensional electron gas is behaving like a degenerate, intensely magnetized ideal electron gas, whose exact equations of state enforce precisely this behavior. The ideal gas even gives a good description of the QHE behavior outside the plateaus: the spikes of the longitudinal resistivity and the various slope and minimum relations connect H and , where it might not have been expected. Localization and delocalization of electrons in the QHE occur automatically in the ideal gas as its electrons pass into and out of a thermodynamic particle reservoir. However, renormalization of critical exponents is beyond the scope of this approximation. © 1990 The American Physical Society.