Optimum ground states for spin-3/2 ladders with two legs

TL;DR

This paper constructs the exact ground state for an antiferromagnetic spin-3/2 two-leg ladder model, revealing its properties and calculating key correlations and fluctuations analytically.

Contribution

It introduces an exact ground state solution for a spin-3/2 ladder model with variable anisotropy, expanding understanding of such quantum spin systems.

Findings

Ground state is unique for most anisotropy values.

Ground state exhibits zero sublattice magnetization.

Correlation functions decay exponentially with distance.

Abstract

We construct the exact ground state for an antiferromagnetic spin-3/2 model on the two-leg ladder as an optimum ground state. The ground state contains a discrete parameter "sigma"=+/-1 and a continuous parameter "a" which controls z-axis anisotropy. For most values of "a" the global ground state is unique. It has vanishing sublattice magnetization and exponentially decaying correlation functions. By using the transfer matrix technique, we calculate exactly the fluctuations of the magnetization, the nearest-neighbour correlation, and the longitudinal correlation length as functions of the parameters.