Spin liquid near the Mott transition in a moire triangular lattice
In plain words
Computer studies of electrons on a triangular lattice predict that just on the insulating side of the metal-insulator transition the spins may form a spin liquid (no magnetic order even at zero temperature), and moire semiconductors could test this.
Precise statement
DMRG studies of the half-filled triangular-lattice Hubbard model find a non-magnetic phase at intermediate $U/t$ between the metal and the 120-degree antiferromagnet, identified as a chiral spin liquid by Szasz et al. (PRX 10, 021042, 2020) and as a different spin liquid by Shirakawa et al. (2017). Determine whether a moire TMD Mott insulator tuned close to the Mott transition realizes such a phase: absence of magnetic order down to $T << J$ ($J$ the exchange scale), a spontaneous zero-field Kerr or Hall signal if time reversal is broken, and the nature of spin excitations. An answer is a measured magnetic phase diagram versus effective $U/t$; the ground state of the Hubbard model itself belongs to the correlated-electron slice.
What would settle it
Magneto-optical measurements of spin susceptibility and spontaneous Kerr rotation versus displacement field near the Mott transition at temperatures well below the exchange scale.