INTERCHANNEL SCATTERING AND INTERIOR CONTACTS IN THE QUANTUM HALL-EFFECT

We extend the model of McEuen et al. based on Buttiker's edge channel approach of the quantum Hall effect to predict the resistances measured on interior contacts, taking interchannel scattering into account by attaching fictitious voltage probes to the Hall conductor. It is shown that interior contacts are very sensitive probes of the interchannel scattering. Between the i = 2 and i = 3 Hall plateaux, the interchannel scattering length L(scatt) is found to vary quasi-exponentially with the magnetic field B, with a value of L(scatt) = 0.5 mm at B = 3.5 T to L(scatt) = 10 mm at B = 4.3 T.