Frustration driven Josephson phase dynamics

TL;DR

This paper reveals that frustrated Josephson systems exhibit oscillating phase dynamics driven by parameter changes, providing insights into complex superconducting phase behavior without harmonic drives.

Contribution

It demonstrates that oscillating Josephson phase dynamics are a general feature of frustrated systems driven through ground state transitions, expanding understanding of superconducting phase behavior.

Findings

Oscillating phase dynamics occur in frustrated Josephson systems.

Transitions between ground states induce phase oscillations.

Different transition types produce varied harmonic content.

Abstract

The Josephson equations predict remarkable effects concerning the phase state of a superconducting junction with an oscillating current induced by a static voltage. Whether the paradigm can be twisted by yielding an oscillating voltage without making use of harmonic drives is a fundamentally relevant problem yet not fully settled. Here, we demonstrate that a dynamical regime with an oscillating phase evolution is a general hallmark of driven Josephson systems exhibiting sign competition in the Josephson couplings. We show that in frustrated Josephson systems an oscillating phase dynamics gets switched on by driving the changeover among different ground states, which can be induced by varying the parameters that set the phase state. Remarkably, the character of the transitions in the Josephson phase space allows different types of dynamics, with few or several harmonics. This result sets out a characteristic mark of any superconducting system with frustrated Josephson couplings and can be exploited to disentangle the complexity of the underlying phases.