Distributed array of josephson devices with coherence

Abstract

Josephson devices are distributed in series in a transmission line structure in which electromagnetic waves are used to synchronize the dynamics of the Josephson devices in order to achieve coherence between the devices. Electromagnetic waves, such as oscillatory traveling waves, standing waves, and solitary waves along the transmission line couple the Josephson devices in a manner such that coherence is achieved for the entire array. The Josephson devices can be tunnel junctions, point contacts, micro bridges, and weak links, and more generally include any such superconductive device which obeys the Josephson equations of voltage and current. The transmission line is any line which controllably supports electromagnetic waves, and can include strip lines located over a ground plane, coaxial lines, etc. A DC bias is supplied to the transmission line, and the ends are terminated in accordance with the type of wave to be propagated along the line. Each Josephson device couples to the electromagnetic wave along the transmission line where many Josephson devices can be in series. Typically, the Josephson devices are spaced closer than the wavelength of the electromagnetic wave, although this is not a necessity. The coherent array can be used for wave generation and detection, amplification, and as a voltage standard.