SWITCHING AND HYSTERESIS IN QUANTUM-DOT ARRAYS

We investigated the low temperature transport properties of AlGaAs/GaA s 200 x 200 quantum dot arrays. The coupling between dots and the elec tron density are controlled by a single gate covering the array. Below 1 K, the current-voltage (C-V) curves show multiple discontinuous jum ps in the current, or 'switching events', between different insulating and conducting states, which occur at gale-voltage and temperature de pendent thresholds. Each single switching event is accompanied by hyst eresis, and multiple switching events result in a hierarchy of hystere sis loops. A possible mechanism for this behavior, involving gate-to-d ot tunneling, is discussed.