Elastic contribution to interaction of vortices in uniaxial superconductors

TL;DR

This paper investigates how elastic stresses from vortices influence their interactions in uniaxial superconductors, leading to lattice distortions and observable magnetization jumps.

Contribution

It introduces the role of elastic stress contributions to vortex interactions and predicts lattice distortions and magnetization discontinuities in uniaxial superconductors.

Findings

Elastic stresses affect vortex interactions depending on orientation and elastic moduli.

Strong stress dependence can distort vortex lattice structures.

Magnetization exhibits a discontinuous jump at the transition from Meissner to mixed states.

Abstract

The stress caused by vortices in tetragonal superconductors contributes to the intervortex interaction which depends on vortex orientation within the crystal, on elastic moduli, and is attractive within certain angular regions even in fields along the $c$ crystal axis. For sufficiently strong stress dependence of the critical temperature, this contribution may result in distortions of the hexagonal vortex lattice for $\bm H||\bm c$. In small fields it leads to formation of a square vortex lattice with a fixed $H$ independent spacing. This should be seen in the magnetization $M(H)$ as a discontinuous jump of magnetization at the transition from the Meissner to mixed states.