Dipolar phase transitions in the cavity with Majorana populated Josephson junctions

TL;DR

This paper investigates the quantum electrodynamics of a microwave cavity coupled with Majorana-populated Josephson junctions, revealing a $\

Contribution

It introduces an effective $\

Findings

Emergence of an effective $\

Strong anharmonicity of the cavity mode due to phase transition

Prediction of instantonic electromagnetic field behavior at finite temperatures

Abstract

We found that QED in the lowest eigenstate of the microwave-cavity, capacitively coupled with Majorana populated Josephson junctions array, is described with an effective $\phi^{4}$ model emerging in the finite domain of the system parameters. Strong anharmonicity of the cavity mode arises due to electric-dipole phase transition facilitated by the single-electron zero mode and Cooper pair tunneling between superconducting islands. An instantonic meandering of the electromagnetic field potential at finite temperatures is predicted.