The Dimer-Hole-RVB State of the 2-Leg t-J Ladder: A Recurrent Variational Ansatz

TL;DR

This paper introduces a variational approach combining dimer and hard-core boson models to study the ground state of the 2-leg t-J ladder, revealing how hole pair structures vary with doping levels.

Contribution

It develops a recurrent variational ansatz that simplifies computations and accurately predicts ground state energies, aligning with numerical methods.

Findings

Good agreement with DMRG results for ground state energy

Hole pair structure varies with doping level

Method effectively captures local pairing structures

Abstract

We present a variational treatment of the ground state of the 2-leg t-J ladder, which combines the dimer and the hard-core boson models into one effective model. This model allows us to study the local structure of the hole pairs as a function of doping. A second order recursion relation is used to generate the variational wave function, which substantially simplifies the computations. We obtain good agreement with numerical density matrix renormalization group results for the ground state energy in the strong coupling regime. We find that the local structure of the pairs depends upon whether the ladder is slightly or strongly dopped.