Magnetic properties of the S = 1 Kitaev model with anisotropic interactions

TL;DR

This paper explores the magnetic behavior of the S=1 Kitaev model under anisotropic interactions by deriving an effective Hamiltonian through perturbation theory and analyzing ground states with exact diagonalization.

Contribution

It introduces a fourth-order perturbation approach to derive an effective Hamiltonian for the anisotropic S=1 Kitaev model, providing new insights into its low-energy physics.

Findings

Low-energy physics described by free spins with an effective magnetic field.

Ground-state properties characterized using exact diagonalization.

Effective Hamiltonian captures anisotropic interaction effects.

Abstract

We investigate magnetic properties in the $S=1$ Kitaev model in the anisotropic limit. Performing the fourth-order perturbation expansion with respect to the $x$-bonds, $y$-bonds, and magnetic field, we derive the effective Hamiltonian, where the low-energy physics should be described by the free spins with an effective magnetic field. Making use of the exact diagonalization method for small clusters, we discuss ground-state properties in the system complementary.