Superconductivity in doped two-leg ladder cuprates

TL;DR

This paper investigates superconductivity in doped two-leg ladder cuprates using the t-J ladder model, revealing how doping induces a transition from a spin-liquid to a superconducting state with a doping-dependent transition temperature.

Contribution

It introduces a kinetic energy driven mechanism for superconductivity in doped two-leg ladder cuprates and describes the doping dependence of the transition temperature.

Findings

Superconductivity emerges from a spin-liquid ground state upon doping.

The transition temperature increases with doping in the underdoped regime.

Maximum transition temperature occurs at optimal doping.

Abstract

Within the t-J ladder model, superconductivity with a modified d-wave symmetry in doped two-leg ladder cuprates is investigated based on the kinetic energy driven superconducting mechanism. It is shown that the spin-liquid ground-state at the half-filling evolves into the superconducting ground-state upon doping. In analogy to the doping dependence of the superconducting transition temperature in the planar cuprate superconductors, the superconducting transition temperature in doped two-leg ladder cuprates increases with increasing doping in the underdoped regime, and reaches a maximum in the optimal doping, then decreases in the overdoped regime.