Character of ground state of an aperiodic frustrated Josephson junction array

TL;DR

This paper investigates the energy spectrum of an aperiodic Josephson junction ladder under magnetic frustration, revealing quasiperiodic behavior influenced minimally by short-range correlations.

Contribution

It introduces a model that describes the energy spectrum considering incommensurate plaquettes independently, highlighting the effects of aperiodicity and incommensurability.

Findings

Energy spectrum is quasiperiodic in frustration.

Short-range correlations have limited impact on the spectrum.

Model effectively describes deep minima in the energy spectrum.

Abstract

We study the energy spectrum for an aperiodic Josephson junction ladder, as a function of frustration. Frustration is brought about by application of a transverse magnetic field, and aperiodicity is imposed by the arrangement of plaquettes with two incommensurate areas. We study the effect of the incommensurate plaquette areas in conjunction with that of the aperiodicity. The structure of the energy spectrum at deep minima is shown to be described by a model that treats the plaquettes independently. The energy spectrum is a quasiperiodic function of frustration; short range correlations in the arrangement of plaquettes have a small effect on the energy power spectrum.