Quantum Resistive Behaviors in the Vortex Liquid Regimes at Finite Temperatures

TL;DR

This paper investigates quantum fluctuation effects on resistive behaviors in vortex liquid regimes of superconductors, revealing a sharp vortex-glass transition and analyzing doping dependence and disorder effects through theoretical modeling and data fitting.

Contribution

It incorporates quantum fluctuations and vortex pinning into GL theory to explain resistive behaviors and transition sharpness, providing new insights into vortex dynamics in superconductors.

Findings

Resistivity shows a sharp drop at a 3D vortex-glass transition, not broadening.

In-plane coherence length decreases approaching underdoped cuprates.

Condensation energy peaks near optimal doping and is linked to fluctuation effects.

Abstract

Motivated by a {\it mean field-like} resistive behavior in magnetic fields commonly seen in various superconducting (SC) cuprates and organics with strong fluctuation, {\it quantum} SC fluctuation effects on resistive behaviors are reexamined by putting emphasis on their roles in the so-called {\it thermal} vortex liquid regime. By incorporating the quantum fluctuation and a vortex pinning effect in the GL fluctuation theory, it is found that the resistivity curve shows not a fan-shaped broadening but a sharp drop at a 3d vortex-glass transition point far below an apparent upper critical field H_{c2}^*(T) as a result of a quantm fluctuation enhanced by an adequately small condensation energy or by a strong field. Fittings to data of cuprate and organic superconductors are performed by including effects of SC pseudogap region. It is argued on the cuprate materials that, irrespective of the presence of fluctuations of competing non-SC orders, the in-plane coherence length of hole-doped cuprates decreases on approaching the underdoped limit and that the condensation energy density to be measured from the heat capacity data is maximum near the optimal doping. The case of disordered quasi 2d s-wave films showing the field-tuned superconductor-insulator transition (FSIT) behavior is also studied for comparison, and an agreement with available data is found.