Strength of the d_{x^2-y^2} pairing in the two-leg Hubbard ladder

TL;DR

This paper uses Quantum Monte Carlo calculations to demonstrate that the doped two-leg Hubbard ladder exhibits strong d_{x^2-y^2} pairing correlations at low temperatures, indicating significant pairing strength.

Contribution

The study provides the first quantitative analysis of the strength and temperature scale of d_{x^2-y^2} pairing correlations in the doped Hubbard ladder using QMC.

Findings

Resonant particle-particle scattering occurs in the d_{x^2-y^2} channel at low temperatures.

Pairing correlations are found to be strong in the Hubbard ladder.

The results suggest significant pairing tendencies relevant to high-temperature superconductivity.

Abstract

In the ground state of the doped two-leg Hubbard ladder there are power-law decaying d_{x^2-y^2}-type pairing correlations. It is important to know the strength and the temperature scale of these correlations. For this purpose, we have performed determinantal Quantum Monte Carlo (QMC) calculations of the reducible particle-particle interaction in the Hubbard ladder. In this paper, we report on these calculations and show that, at sufficiently low temperatures, resonant particle-particle scattering takes place in the d_{x^2-y^2} pairing channel for certain values of the model parameters. The QMC data presented here indicate that the d_{x^2-y^2} pairing correlations are strong in the Hubbard ladder.