Effect of zero energy bound states on macroscopic quantum tunneling in high-Tc superconductor junctions

TL;DR

This paper investigates how zero energy bound states at interfaces in high-Tc superconductor Josephson junctions suppress macroscopic quantum tunneling due to increased quasiparticle dissipation.

Contribution

It provides an analytical formula for the MQT rate and demonstrates the impact of ZES on tunneling suppression in high-Tc superconductor junctions.

Findings

ZES cause strong Ohmic quasiparticle dissipation.

MQT rate is significantly reduced in junctions with ZES.

Absence of ZES in c-axis junctions results in higher MQT rates.

Abstract

The macroscopic quantum tunneling (MQT) in the current biased high-Tc superconductor Josephson junctions and the effect of the zero energy bound states (ZES) on the MQT are theoretically investigated. We obtained the analytical formula of the MQT rate and showed that the presence of the ZES at the normal/superconductor interface leads to a strong Ohmic quasiparticle dissipation. Therefore, the MQT rate is noticeably inhibited in compared with the c-axis junctions in which the ZES are completely absent.