[PDF] from aps.org Dynamical Mean-Field Theory of Moiré Bilayer Transition Metal Dichalcogenides: Phase Diagram, Resistivity, and Quantum Criticality

Jiawei Zang, Jie Wang, Jennifer Cano, Antoine Georges, Andrew Millis

Abstract:

We present a comprehensive dynamical mean field study of the triangular lattice moir´e Hubbard model,
which is believed to represent the physics of moir´e bilayer transition metal dichalcogenides. In these
materials, important aspects of the band structure including the bandwidth and the order and location of van
Hove singularities can be tuned by varying the interlayer potential. We present a magnetic and metalinsulator phase diagram and a detailed study of the dependence of the resistivity on temperature, band
filling, and interlayer potential. We find that transport displays Fermi liquid, strange metal, and quantum
critical behaviors in distinct regions of the phase diagram. Specifically, we find that the cube-root van Hove
singularity [ρðϵÞ ∼ jϵj
−1=3] gives a strange metal behavior with a T-linear scattering rate and ω=T scaling.
We show how magnetic order affects the resistivity. Our results elucidate the physics of the correlated states
and the metal-insulator continuous transition recently observed in twisted homobilayer WSe2 and
heterobilayer MoTe2=WSe2 experiments.