Spontaneous and stimulated emission tuning characteristics of a Josephson junction in a microcavity

TL;DR

This paper theoretically explores how a Josephson junction in a microcavity can be tuned for controlled photon emission, with potential applications in quantum technologies.

Contribution

It introduces a theoretical analysis of emission tuning in Josephson junctions within microcavities, including relationships between magnetic induction, voltage, and emission characteristics.

Findings

Linear relationship between magnetic induction and voltage for spontaneous emission

Oscillatory dependence of stimulated emission rate on phase difference

Calculated emission maxima and resonances for controlled photon production

Abstract

We have investigated theoretically the tuning characteristics of a Josephson junction within a microcavity for one-photon spontaneous emission and for one-photon and two-photon stimulated emission. For spontaneous emission, we have established the linear relationship between the magnetic induction and the voltage needed to tune the system to emit at resonant frequencies. For stimulated emission, we have found an oscillatory dependence of the emission rate on the initial Cooper pair phase difference and the phase of the applied field. Under specific conditions, we have also calculated the values of the applied radiation amplitude for the first few emission maxima of the system and for the first five junction-cavity resonances for each process. Since the emission of photons can be controlled, it may be possible to use such a system to produce photons on demand. Such sources will have applications in the fields of quantum cryptography, communications and computation.