TIME-DEPENDENT THEORY OF A DOUBLE QUANTUM-WELL RESONANT INTERBAND TUNNEL TRANSISTOR

A time-dependent theory of a double quantum well resonant interband tu nnel transistor is presented. The theory is based on a system of three linear differential equations for time-dependent resonant currents an d charges stored in the wells. First the stationary resonant current-v oltage curve is investigated. Then the general solution for the non-st ationary tunnelling current is obtained by the perturbation method. Th e current is found to be an ultra-sensitive function of the time-depen dent small external voltage which is applied between the emitter and t he second quantum well for detuning the resonances of quantum levels. Two non-stationary cases are investigated. For a step-function impulse of external voltage the characteristics of the response current are f ound. For a harmonic external voltage the frequency dependence of the response current is found. Matched and unmatched systems of barriers a re investigated and found to exhibit significantly different behaviour s.