Theory of Macroscopic Quantum Dynamics in High-Tc Josephson Junctions

TL;DR

This paper theoretically analyzes macroscopic quantum tunneling in s-wave/d-wave Josephson junctions, revealing suppressed quasiparticle dissipation and highlighting their potential for quantum information applications.

Contribution

It introduces a theoretical framework showing that s-wave/d-wave hybrid junctions have reduced dissipation compared to d-wave/d-wave junctions, due to quasiparticle-tunneling blockade.

Findings

Suppressed quasiparticle dissipation in s-wave/d-wave junctions

Potential for high-coherence quantum devices

Contrast with higher dissipation in d-wave/d-wave junctions

Abstract

We have theoretically investigated macroscopic quantum tunneling (MQT) and the influence of nodal quasiparticles and zero energy bound states (ZES) on MQT in s-wave/d-wave hybrid Josephson junctions. In contrast to d-wave/d-wave junctions, the low-energy quasiparticle dissipation resulting from nodal quasiparticles and ZES is suppressed due to a quasiparticle-tunneling blockade effect in an isotropic s-wave superconductor. Therefore, the inherent dissipation in these junctions is found to be weak. This result suggests high potential of s-wave/d-wave hybrid junctions for applications in quantum information devices.