Fluctuation Effects in Underdoped Cuprate Superconductors under Magnetic Field

TL;DR

This paper investigates the complex fluctuation effects in underdoped cuprate superconductors under magnetic fields, highlighting the roles of thermal and quantum fluctuations and their impact on resistivity and Nernst measurements.

Contribution

It introduces a comprehensive analysis including quantum dynamical fluctuations and pseudogap effects to explain experimental data in underdoped cuprates.

Findings

Quantum dynamical fluctuations significantly affect vortex states.

The pseudogap region influences the Nernst coefficient and coherence length.

Resistivity and Nernst data are well fitted by the theoretical model.

Abstract

Fluctuation effects in underdoped cuprates under high fields are examined by trying to fit theoretical results to resistivity and Nernst data in vortex states. The superconducting (SC) fluctuation in underdoped cuprates includes not only the ordinary thermal contribution but also a large amount of quantum dynamical contributions. Together with this, the presence of a SC pseudogap region T_0-T_{c0} increasing with underdoping is found to be the origin of the Nernst coefficient becoming anomalously smaller and the in-plane coherence length {\it apparently} increasing with underdoping.