Electrodynamics of the Josephson-Coupled Parallel Plate Resonator

TL;DR

This paper investigates the eigen oscillations of a superconducting parallel plate resonator with Josephson coupling, revealing how resonant frequency and Q-factor vary with insulator thickness and identifying a crossover between wave types.

Contribution

It provides a detailed analysis of the electrodynamics in Josephson-coupled resonators, highlighting the non-monotonic behavior of key parameters and the crossover phenomena.

Findings

Resonant frequency and Q-factor vary non-monotonically with insulator thickness.

A crossover between Swihart waves and Josephson plasmons occurs at a specific thickness.

Global minimum in frequency and maximum in Q-factor observed at S~10ξ.

Abstract

Eigen oscillations in a superconducting parallel plate resonator with the Josephson-coupled plates are investigated. While the insulator thickness S changes from tens of microns down to the decay lengthscale of the superconducting wavefunction into a dielectric, \xi~1 nm, both the resonant frequency and Q-factor vary non-monotonically by up to three orders in magnitude. A crossover between the Swihart waves and Josephson plasmons causes a global minimum in the resonant frequency and a local maximum in the Q-factor at S~10\xi.