Anisotropy as a diagnostic test for distinct tensor network wavefunctions of integer and half-integer spin Kitaev quantum spin liquids

TL;DR

This paper investigates the fundamental differences between integer and half-integer spin quantum spin liquids in the Kitaev model, revealing that spatial anisotropy can serve as a diagnostic tool to distinguish these states through tensor network wavefunctions.

Contribution

The study introduces the use of tensor network wavefunctions to differentiate integer and half-integer spin quantum spin liquids, highlighting the role of sign structures and anisotropy as diagnostic indicators.

Findings

Sign structures of tensor network wavefunctions differ for integer and half-integer spins.

Spatial anisotropy can distinguish between these quantum spin liquids.

Numerical methods confirm the theoretical predictions.

Abstract

Contrasting ground states of quantum magnets with the integer and half-integer spin moments are the manifestation of many-body quantum interference effects. In this work, we investigate the distinct nature of the integer and half-integer spin quantum spin liquids in the framework of the Kitaev's model on the honeycomb lattice. The models with arbitrary spin quantum numbers are not exactly solvable in contrast to the well-known quantum spin liquid solution of the spin-1/2 system. We use the tensor network wavefunctions for the integer and half-integer spin quantum spin liquid states to unveil the important difference between these states. We find that the distinct sign structures of the tensor network wavefunction for the integer and half-integer spin quantum spin liquids are responsible for completely different ground states in the spatially anisotropic limit. Hence the spatial anisotropy would be a useful diagnostic test for distinguishing these quantum spin liquid states, both in the numerical computations and experiments on real materials. We support this discovery via extensive numerics including the tensor network, DMRG, and exact diagonalization computations.