Angular dependence of the melting of the porous vortex matter in $\mathrm{Bi_{2}Sr_{2}CaCu_{2}O_{8}}$

TL;DR

This study investigates how the melting behavior of vortex matter in Bi2Sr2CaCu2O8 is influenced by the angle of magnetic field relative to columnar defects, revealing angle-independent thermodynamics but angle-dependent dynamics.

Contribution

It demonstrates that vortex pancakes stay localized along columnar defects at various angles, maintaining thermodynamic properties, while vortex kink sliding affects irreversible behaviors.

Findings

Thermodynamic lines are angle independent.

Vortex pancakes remain localized along defects at large angles.

Dynamic properties are significantly affected by field tilt.

Abstract

The behavior of vortex matter in $\mathrm{Bi_{2}Sr_{2}CaCu_{2}O_{8}}$ in the presence of a low concentration of tilted columnar defects (CDs) was studied using magneto-optical measurements and molecular dynamics simulations. We find that while the dynamic properties are significantly affected by tilting the field away from CDs, the thermodynamic lines are angle independent. Our simulations reveal that vortex pancakes remain localized along CDs even at large tilting angles thus preserving the thermodynamic features, while suppression of irreversible properties is caused by vortex kink sliding.