Electrical rectification by magnetic edge states

We investigate electron channelling by inhomogeneous magnetic fields in hybrid semiconductor/ferromagnet structures. A novel type of rectifying behaviour is observed in the current-voltage characteristics measured along the drift path of magnetic edge states. This rectification effect is switched on by the application of the magnetic potential and changes sign with its polarity. We ascribe this non-linear behaviour to the anisotropic electron-phonon interaction arising from the asymmetry of the energy dispersion curves of snake orbits that results in electrons thermalising by emitting phonons along the electron drift direction, We present a theory to evaluate the electromotive force due to this phonon drag effect and compare it to the non-linear behaviour. (C) 2002 Elsevier Science B.V. All rights reserved.