Comparative study of the pressure effects on the magnetic penetration depth in electron- and hole-doped cuprate superconductors

TL;DR

This study compares how pressure influences the magnetic penetration depth in hole- and electron-doped cuprate superconductors, revealing significant differences that shed light on their distinct electronic properties and doping asymmetries.

Contribution

It provides experimental evidence of contrasting pressure effects on the penetration depth in hole- and electron-doped cuprates, highlighting their different electron-phonon coupling characteristics.

Findings

Large change in λ in hole-doped YBa2Cu3O(7-d) under pressure

No significant λ change in electron-doped Sr0.9La0.1CuO2 under pressure

Suggests different electron-phonon coupling mechanisms in the two types of cuprates

Abstract

The effect of pressure on the magnetic penetration depth $\lambda$ was tested in the hole-doped superconductor YBa2Cu3O(7-d) and in the electron-doped one Sr0.9La0.1CuO2 by means of magnetization measurements. Whereas a large change of $\lambda$ was found in YBa2Cu3O(7-d), confirming the non-adiabatic character of the electron-phonon coupling in hole-doped superconductors, the same quantity is not affected by pressure in the electron-doped Sr0.9La0.1CuO2, suggesting a close similarity of the latter to conventional adiabatic BCS superconductors. The present results imply a remarkable difference between the electronic properties of hole-doped cuprates and the electron-doped Sr0.9La0.1CuO2, giving a strong contribution to the long debated asymmetric consequences of hole- and electron-doping in cuprate superconductors.