Quantum Matter Seminar

Cuprates and quantum hall systems are two prominent examples of strongly correlated systems. The emerging fields of Moire systems, where 2 crystalline patterns interfere to form a long period modulation, meanwhile shed new light on strong correlation physics. In this talk I'll describe 2 gapless states, arising from symmetry constraints, in Moire cuprate systems and half-filled Landau levels under long-wavelength modulations.

Twisted cuprates hold promise for high Tc topological superconductivity, with potential implications for quantum computing. While previous predictions are based on simple weakly interacting models, here we examine the vital role played by realistic aspects and strong correlations that impact the resulting ground states and report a gapless chiral superconductor. We discuss signatures which are being studied in ongoing experiments.

Next we show that quantum electrodynamics (QED_3) emerges in the simple setup of Dirac materials on a vortex lattice.  Chemical potential modulation further drives a fractional quantum hall transition, at charge-neutrality for the Dirac electrons. Physical observables and numerical prospects are discussed. The discussion potentially relates to ongoing experiments of a topological insulator surface proximate to type-II superconductors.