Dr. Michael Knap
TU Munich
Chiral Pseudo Spin Liquids in Moiré Heterostructures
Location: Zoom
Faculty Host: Brian Skinner
Abstract: We propose multilayer moiré structures in strong external magnetic fields as a novel platform for realizing highly tunable, frustrated Hubbard physics with topological order. Identifying the layer degree of freedom as a pseudospin allows us to retain SU(2) symmetry while controlling ring-exchange processes and concurrently quenching the kinetic energy by large external magnetic fields. This way, a broad class of interacting Hubbard-Hofstadter states and their transitions can be studied. Remarkably, in the limit of strong interactions the system becomes Mott insulating and we find chiral pseudospin-liquid phases which are induced by the magnetic field. We find that this topologically ordered state remains exceptionally stable toward relevant perturbations. We discuss how layer pseudospin can be probed in near-term experiments. We furthermore analyze the dynamical response of the chiral pseudo-spin liquid and other nearby phases, that can be measured for example with quantum twisting microscopes. As the magnetic flux can be easily tuned in moiré systems, our approach provides a promising route toward the experimental realization and control of topologically ordered phases of matter.
[1] Kuhlenkamp, et al. Phys. Rev. X 14, 021013 (2024)
[2] Pichler, et al. Phys. Rev. B 111, 075108 (2025)
[3] Kadow, et al. Phys. Rev. B 106, 094417 (2022)
Zoom details:
Password: 3.14159
