Electric field effect modulation of transition temperature, mobile carrier density and in-plane penetration depth in NdBa2Cu3O(7-delta) thin films

TL;DR

This study investigates how electric fields influence the critical temperature, carrier density, and penetration depth in thin NdBa2Cu3O(7-delta) films, revealing a quantum superconductor-insulator transition.

Contribution

It demonstrates the linear dependence of T_c on carrier density and penetration depth, providing evidence for a quantum superconductor-insulator transition in two dimensions.

Findings

T_c depends linearly on n_2D and lambda_ab(0)

Evidence of a quantum superconductor-insulator transition

Identifies critical behavior near the transition

Abstract

We explore the relationship between the critical temperature, T_c, the mobile areal carrier density, n_2D, and the zero temperature magnetic in-plane penetration depth, lambda_ab(0), in very thin underdoped NdBa2Cu3O{7-delta} films near the superconductor to insulator transition using the electric field effect technique. We observe that T_c depends linearly on both, n_2D and lambda_ab(0), the signature of a quantum superconductor to insulator (QSI) transition in two dimensions with znu-bar where z is the dynamic and nu-bar the critical exponent of the in-plane correlation length.