Optimum ground states for spin-$\frac{3}{2}$ chains

TL;DR

This paper constructs exact matrix product ground states for spin-3/2 chains, revealing three distinct phases with detailed physical properties, advancing understanding of quantum spin chain ground states.

Contribution

It introduces a class of exact ground states for spin-3/2 chains in matrix product form, identifying three phases and analyzing their properties.

Findings

Identified three phases: weak antiferromagnet, weak ferromagnet, dimerized antiferromagnet.

Calculated magnetization and two-spin correlations exactly.

Revealed a rich structure of phase behavior depending on model parameters.

Abstract

We present a set of {\em optimum ground states} for a large class of spin-$\frac{3}{2}$ chains. Such global ground states are simultaneously ground states of the local Hamiltonian, i.e. the nearest neighbour interaction in the present case. They are constructed in the form of a matrix product. We find three types of phases, namely a {\em weak antiferromagnet}, a {\em weak ferromagnet}, and a {\em dimerized antiferromagnet}. The main physical properties of these phases are calculated exactly by using a transfer matrix technique, in particular magnetization and two spin correlations. Depending on the model parameters, they show a surprisingly rich structure.