A quantum spin liquid phase in the Kitaev-Hubbard model

TL;DR

This paper identifies a quantum spin liquid phase in the Kitaev-Hubbard model near the Mott transition, using advanced computational methods, highlighting potential real materials for experimental realization.

Contribution

It demonstrates the existence of a QSL phase in the Kitaev-Hubbard model near the Mott transition using fermionic PEPS calculations, providing insights into material candidates.

Findings

QSL phase exists near the Mott insulator transition.

First-order transition from QSL to semi-metal phase.

Potential for experimental realization in Iridium oxides.

Abstract

The quantum spin liquid (QSL) state has been searched intensively in Kitaev-like materials, such as the Iridium oxides $A_2$IrO$_3$ and $\alpha$-RuCl$_3$. The half-filled Kitaev-Hubbard model with bond dependent hopping terms is used to describe the Kitaev-like materials, which is calculated using the state-of-the-art fermionic projected entangled pair states (fPEPS) method. We find a QSL phase near the Mott insulator transition, which has a strong first-order transition to the semi-metal phase with the decrease of Hubbard $U$. We suggest that a promising routine to find the QSL is to find the Iridium oxides that are near the Mott insulator transitions.