A Possible Quantum Spin Liquid Phase in the Kitaev–Hubbard Model

The quantum spin liquid (QSL) state of Kitaev-like materials, such as iridium oxides A₂IrO₃ and α-RuCl₃, has been explored in depth. 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 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 approach to finding QSL states is by finding iridium oxides that are near the Mott insulator transition.