Dynamic Hall effect as a mechanism for self-sustained oscillations and chaos in semiconductors

We propose a novel mechanism which explains self-generated voltage or current oscillations induced by a transverse magnetic field on the basis of a dynamic Hall effect coupled with impact ionization. Dielectric relaxation of both the applied electric field and the Hall field combined with the generation-recombination kinetics of the carrier density yields oscillatory instabilities at a threshold value of the magnetic field. General analytic conditions and numerical simulations for p-Ge at 4 K are presented, exhibiting Hopf bifurcations, period-doubling routes to chaos, and type-I intermittency.