Dynamic transition and Shapiro-step melting in a frustrated Josephson-junction array

TL;DR

This paper investigates how thermal fluctuations cause melting of Shapiro steps and induce dynamic phase transitions in a frustrated Josephson-junction array under combined currents, revealing their interconnected nature.

Contribution

It introduces a detailed analysis of the interplay between mode locking, Shapiro step melting, and dynamic phase transitions at finite temperatures in a 2D Josephson-junction array.

Findings

Thermal fluctuations lead to melting of Shapiro steps.

Dynamic phase transition accompanies the melting process.

Universality class of the transition is discussed.

Abstract

We consider a two-dimensional fully frustrated Josephson-junction array driven by combined direct and alternating currents. Interplay between the mode locking phenomenon, manifested by giant Shapiro steps in the current-voltage characteristics, and the dynamic phase transition is investigated at finite temperatures. Melting of Shapiro steps due to thermal fluctuations is shown to be accompanied by the dynamic phase transition, the universality class of which is also discussed.