Special 290S/290K Quantum Materials Seminar speaker Johannes Motruk (University of Geneva) Friday, May 26 at 11 am in 402 Physics South

Time/Venue Friday, May 26 at 11:00 am in 402 Physics South and via Zoom:
https://berkeley.zoom.us/j/99523499113pwd=REovb3pyam03WXQwbEhrU3dqNHZvdz09
Meeting ID: 995 2349 9113 Passcode: 600704
Host Joel Moore
Title Kagome chiral spin liquid in transition metal dichalcogenide moiré bilayers
Abstract In this talk, I will present results on the state at n=3/4 filling of the flat band in transition metal dichalcogenide moiré bilayers. At this filling, the system develops charge order in a kagome pattern resulting in localized spins on this lattice geometry. Starting from an extended Hubbard model description, we derive an effective spin model on the kagome lattice and find that its further neighbor spin interactions can be much less suppressed than the corresponding electron hopping strength. Using density matrix renormalization group simulations, we study its phase diagram and, for realistic model parameters relevant for WSe2/WS2, we show that this material can realize the exotic chiral spin liquid phase and the highly debated kagome spin liquid. Our work thus demonstrates that the frustration and strong interactions present in TMD heterobilayers provide a novel experimental realization of kagome spin models, representing an exciting platform to study spin liquid physics.