Bloch oscillating transistor—a new mesoscopic amplifier

Bloch oscillating transistor (BOT) is a novel, three-terminal Josephson junction device. Its operating principle utilizes the fact that Zener tunneling up to a higher band will lead to a blockade of coherent Cooper-pair tunneling, Bloch oscillation, in a suitably biased Josephson junction. The Bloch oscillation is resumed only after the junction has relaxed to the lowest band by quasiparticle tunneling. In this paper we present a simple model for the operation of the BOT and calculate its gain in terms of the interband transition rates.