Bona fide interaction-driven topological phase transition in correlated SPT states

Understand

It is expected that the interplay between non-trivial band topology and strong electron correlation will lead to very rich physics.

• Thus a controlled study of the competition between topology and correlation is of great interest.
• Here, employing large-scale quantum Monte Carlo (QMC) simulations, we provide a concrete example of the Kane-Mele-Hubbard (KMH) model on an AA stacking bilayer honeycomb lattice with inter-layer antiferromagnetic interaction.
• Our simulation identified several different phases: a quantum spin-Hall insulator (QSH), a $xy$-plane antiferromagnetic Mott insulator ($xy$-AFM) and an inter-layer dimer-singlet insulator (dimer-singlet).