Tunneling and Universality in the Integer Quantum Hall Effect

Alex Hansen, Janos Kertesz

Published 1997-06-06Version 1

We show analytically and numerically that omission of quantum interference from the Chalker-Coddington model of the integer quantum Hall effect gives a localization length exponent nu=4/3 as in ordinary two-dimensional percolation. Thus, contrary to semi-classical scaling arguments, tunneling alone does not lead to nu=7/3.