A superconducting microwave multivibrator produced by coherent feedback

TL;DR

This paper presents a superconducting microwave circuit with coherent feedback that exhibits bistability and oscillation locking, functioning as a latch, with results matching a new semiclassical modeling software.

Contribution

It introduces a novel superconducting microwave multivibrator using coherent feedback and demonstrates its operation and modeling with a new software tool.

Findings

Demonstrates bistable and astable states in the network

Shows frequency locking of oscillations

Validates observations with a new quantum feedback modeling software

Abstract

We investigate a coherent nonlinear feedback circuit constructed from pre-existing superconducting microwave devices. The network exhibits emergent bistable and astable states, and we demonstrate its operation as a latch and the frequency locking of its oscillations. While the network is tedious to model by hand, our observations agree quite well with the semiclassical dynamical model produced by a new software package [N. Tezak et al., arXiv:1111.3081v1] that systematically interpreted an idealized schematic of the system as a quantum optic feedback network.