Charge density correlations in t-J ladders investigated by the CORE method

TL;DR

This paper applies the CORE method to t-J ladders and cylinders, revealing short-range diagonal stripe correlations through numerical analysis of effective Hamiltonians.

Contribution

It introduces a range-2 effective Hamiltonian approach for t-J ladders using the CORE method with plaquette or rung basis decomposition.

Findings

Short-range diagonal stripe correlations in 4-leg t-J ladders

Agreement of spin gaps and charge correlations with ED and DMRG data

Effective Hamiltonians accurately capture key physical properties

Abstract

Using 4-site plaquette or rung basis decomposition, the CORE method is applied to 2-leg and 4-leg t-J ladders and cylinders. Resulting range-2 effective hamiltonians are studied numerically on periodic rings taking full advantage of the translation symmetry as well as the drastic reduction of the Hilbert space. We investigate the role of magnetic and fermionic degrees of freedom to obtain the most reliable representation of the underlying model. Spin gaps, pair binding energies and charge correlations are computed and compared to available ED and DMRG data for the full Hamiltonian. Strong evidences for short-range diagonal stripe correlations are found in periodic 4-leg t-J ladders.