Resonant Tunneling Transmission Characteristics and Tunneling Time in Asymmetrical Double-Barrier Structures with Multiple Prewells

Abstract

Resonant tunneling phenomenon in the asymmetrical double-barrier structures with multiple prewells is studied theoretically. First, analytical expressions for the tunneling transmission coefficient and the resonance condition are derived. Second, analytical expressions for the dwell time and for the shortest dwell time condition are obtained. It is found that the dwell time in the main well region decreases greatly with increasing number of prewells, and that there exists an optimum number of prewells which makes the dwell time in the whole region shortest.