In situ controllable magnetic phases in doped twisted bilayer transition-metal dichalcogenides

Abstract

We study the electronic structure of hole-doped transition metal dichalcogenides for small twist-angels, where the onsite repulsion is extremely strong. Using unbiased diagrammatic Monte Carlo simulations, we find evidence for magnetic correlations which are driven by delocalization, and can be controlled in situ via the dielectric environment. For weak spin-orbit coupling we find that the moderately doped system becomes antiferromagnetic, whilst the regime of strong spin-orbit coupling features ferromagnetic correlations. We show that this behavior is accurately predicted by an analytical theory based on moment expansion of the Hamiltonian, and analysis of corresponding particle trajectories.