Quantum creep in layered antiferromagnetic superconductor

TL;DR

This paper investigates how antiferromagnetic order in layered superconductors influences quantum tunneling of vortices, revealing temperature-dependent effects and conditions for thermal or quantum creep based on magnetic field orientation.

Contribution

It introduces the concept of spin-flop domains affecting vortex quantum tunneling, showing how magnetic order modifies the activation energy and tunneling rates in layered superconductors.

Findings

Quantum tunneling rate becomes temperature dependent below crossover temperature.

Magnetic field direction influences whether thermal or quantum creep occurs.

Activation energy is affected by antiferromagnetic order and spin-flop domains.

Abstract

In the mixed state of layered superconductor the antiferromagnetic order of magnetic ions can create the spin-flop domains along the phase cores of the Josephson vortices. The paper discusses how this feature affects the macroscopic quantum tunnelling of the Josephson vortices. It is shown that the action and hence the activation energy is rendered temperature dependent so that the quantum tunnelling rate becomes temperature dependent below the crossover temperature. It is also shown that in constant temperature thermal or quantum creep may occur, depending on the direction or intensity of the applied magnetic field.