Dynamical Casimir effect in a double tunable superconducting circuit

TL;DR

This paper analyzes particle creation via the dynamical Casimir effect in a superconducting circuit with two tunable SQUIDs, exploring resonance conditions, interference effects, and potential experimental tests.

Contribution

It provides an analytical and numerical study of the dynamical Casimir effect in a double SQUID circuit with time-dependent boundary conditions, highlighting new resonance and interference phenomena.

Findings

Particle creation rate depends on cavity spectrum characteristics.

Parametric resonance conditions enhance particle production.

Interference effects arise from simultaneous boundary condition modulations.

Abstract

We present an analytical and numerical analysis of the particle creation in a cavity ended with two SQUIDs, both subjected to time dependent magnetic fields. In the linear and lossless regime, the problem can be modeled by a free quantum field in $1+1$ dimensions, in the presence of boundary conditions that involve a time dependent linear combination of the field and its spatial and time derivatives. We consider a situation in which the boundary conditions at both ends are periodic functions of time, focusing on interesting features as the dependence of the rate of particle creation with the characteristics of the spectrum of the cavity, the conditions needed for parametric resonance, and interference phenomena due to simultaneous time dependence of the boundary conditions. We point out several concrete effects that could be tested experimentally