  We show that for the case of a many valley host semiconductor an edge channel
(EC) related non-local behaviour can persist also in the 3D-regime where the
quantum Hall effect (QHE) is already quenched. We demonstrate that the QHE is
replaced by conductance fluctuations due to EC backscattering in the contact
arms, which leads to a fluctuating current redistribution between a dissipative
bulk electron system and a less-dissipative EC-system. Both electron systems
are located in different valleys of the band structure. The linear increase of
Rxx with the magnetic field is explained by EC-backscattering in the Hall bar

Materials Science;Mesoscale and Nanoscale Physics