Doping dependence of Meissner effect in cuprate superconductors

TL;DR

This study investigates how doping levels affect the Meissner effect in cuprate superconductors using the t-t'-J model, revealing doping-dependent magnetic properties and the maximum superfluid density near optimal doping.

Contribution

It provides a theoretical analysis of the doping dependence of the Meissner effect in cuprates within the kinetic energy driven mechanism, matching experimental observations.

Findings

Maximal superfluid density occurs near doping δ≈0.195.

Doping influences the magnetic field penetration depth and superfluid density.

The model reproduces key features of the doping and temperature dependence of magnetic properties.

Abstract

Within the t-t'-J model, the doping dependence of the Meissner effect in cuprate superconductors is studied based on the kinetic energy driven superconducting mechanism. Following the linear response theory, it is shown that the electromagnetic response consists of two parts, the diamagnetic current and the paramagnetic current, which exactly cancels the diamagnetic term in the normal state, and then the Meissner effect is obtained for all the temperature $T\leq T_{c}$ throughout the superconducting dome. By considering the two-dimensional geometry of cuprate superconductors within the specular reflection model, the main features of the doping and temperature dependence of the local magnetic field profile, the magnetic field penetration depth, and the superfluid density observed on cuprate superconductors are well reproduced. In particular, it is shown that in analogy to the domelike shape of the doping dependent superconducting transition temperature, the maximal superfluid density occurs around the critical doping $\delta\approx 0.195$, and then decreases in both lower doped and higher doped regimes.