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

Abstract

The effect of pressure on the magnetic penetration depth lambda was tested for the hole-doped superconductor YBa2Cu3O7-delta and in the electron-doped one Sr0.9La0.1CuO2 by means of magnetization measurements. Whereas a large change of lambda was found in YBa2Cu3O7-delta, confirming the non-adiabatic character of the electron-phonon coupling in hole-doped superconductors, the same quantity is not affected by pressure in electron-doped Sr0.9La0.1CuO2, suggesting a close similarity of the latter to conventional adiabatic Bardeen-Cooper-Schrieffer superconductors. The present results imply a remarkable difference between the electronic properties of hole-doped cuprates and electron-doped Sr0.9La0.1CuO2, giving a strong contribution to the long debated asymmetric consequences of hole and electron doping in cuprate superconductors.