DYNAMIC HALL-EFFECT OF HOT-ELECTRONS AS A NOVEL MECHANISM FOR CURRENTOSCILLATIONS, CHAOS AND INTERMITTENCY

Magnetic-field-induced oscillatory instabilities in semiconductors are explained by a novel dynamic Hall effect of hot electrons. The basic new idea is to consider the non-linear dynamics of both the drift and the Hall field due to dielectric relaxation coupled with impact ioniza tion of hot carriers. This results in self-generated current or voltag e oscillations under DC bias, period-doubling, and intermittency route s to chaos. Numerical simulations are presented for p-Ge, n-InSb, and n-GaAs with field-dependent mobilities and one or two shallow impurity levels at 4.2 K. In particular, the universal scaling behaviour of ty pe-I intermittency as a function of magnetic field is demonstrated.