Dynamical Casimir effect in a double tunable superconducting circuit

Abstract

We present an analytical and numerical analysis of the particle creation in a cavity ended with two superconducting quantum interference devices, 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.