One-Dimensional S=1 Spin-Orbital Model with Uniaxial Single-Ion Anisotropy

TL;DR

This paper studies the ground-state properties of a one-dimensional S=1 spin-orbital model, analyzing how exchange couplings and uniaxial anisotropy influence phases using DMRG, and compares results with the S=1/2 case.

Contribution

It provides a detailed phase diagram for the S=1 model with uniaxial anisotropy, extending understanding beyond the S=1/2 case and highlighting anisotropy effects.

Findings

Ground-state energy and correlation functions depend on exchange couplings.

Uniaxial anisotropy significantly alters phase boundaries.

Comparison with S=1/2 model reveals distinct phase behavior.

Abstract

We investigate ground-state properties of a one-dimensional S=1 spin-orbital model with or without uniaxial single-ion anisotropy. By means of the density matrix renormalization group method, we compute the ground-state energy, the magnetization curves and the correlation functions. We discuss how the ground-state properties depend on the two exchange couplings for orbital and spin sectors. The phase diagram obtained is compared with that for the S=1/2 model. We also address the effect of uniaxial single-ion anisotropy.