Transport Properties of Vortex Matter Governed by the Edge Inductance of Superconducting Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8}$ Single Crystals

TL;DR

This study reveals that vortex dynamics in Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8}$ superconductors are governed by edge inductance below a certain transition, enabling ultra-sensitive resistance measurements and clarifying the nature of vortex melting.

Contribution

It demonstrates that the $T_x$ transition is electrodynamic, not thermodynamic, and shows how edge inductance controls vortex flow, allowing detection of extremely low resistances and insights into vortex melting.

Findings

Vortex dynamics below $T_x$ are governed by edge inductance.

Resistive step at vortex melting is due to loss of c-axis correlations.

Resistance can be measured two orders of magnitude below noise level.

Abstract

We study the distribution of transport current across superconducting Bi$_2$Sr$_2$CaCu$_2$O$_8$ crystals and the vortex flow through the sample edges. We show that the $T_x$ transition is of electrodynamic rather than thermodynamic nature, below which vortex dynamics is governed by the edge inductance instead of the resistance. This allows measurement of the resistance down to two orders of magnitude below the transport noise. By irradiating the current contacts the resistive step at vortex melting is shown to be due to loss of c-axis correlations rather than breakdown of quasi-long-range order within the a-b planes.