Probing quantum spin liquids with a quantum twisting microscope*

Quantum spin liquids are elusive states of matter that defy magnetic ordering down to zero temperature. Neutron scattering has been a powerful experimental tool to study the excitations of these states, but it is unsuitable for TMD monolayers, where these states have been recently predicted. Here, we propose a novel technique to image the fractionalized excitations in quantum spin liquids. Our approach is based on a tunneling spectroscopy setup composed of a planar tunneling junction with a magnetic insulator sandwiched between metallic layers. By tuning the relative angle and voltage difference between the metallic layers, we can extract the dynamical spin structure factor of the insulator with both energy and momentum resolution. Our technique offers a promising tool for the experimental identification and characterization of quantum spin liquids in monolayer systems.