Effect of hole doping on the London penetration depth of Bi:2212 and Bi(Y):2212

TL;DR

This study investigates how hole doping affects the London penetration depth in Bi:2212 and Bi(Y):2212 superconductors, revealing that the pseudogap diminishes superconductivity mainly at lower doping levels.

Contribution

It provides experimental data on the relationship between hole doping and the London penetration depth in Bi-based cuprates, highlighting the pseudogap's role in superconducting response.

Findings

Pseudogap weakens superconductivity for p < 0.19

AC susceptibility measurements support the doping dependence

In-plane London penetration depth varies with hole concentration

Abstract

We report measurements of AC susceptibility and hence the in-plane London penetration depth on the same samples of Bi:2212 and Bi(Y):2212 for many values of the planar hole concentration/CuO2 unit (p). These support the scenario in which the pseudogap weakens the superconducting response only for p less than approximately 0.19.