Physics Main Calendar

Abstract: The Wigner crystal (WC) is a prototypical quantum phase that emerges in the strong-coupling, low-density limit of the two-dimensional electron gas. In this talk, I explore the quantum properties of the WC and related phases using an asymptotically exact semiclassical expansion. I first show how an applied magnetic field and intrinsic band Berry curvature modify the magnetic properties of the WC. The relevant exchange processes arise from multi-particle tunneling along complex trajectories, which constitute complex-instanton solutions of the phase-space path integral. As a result, exchange amplitudes acquire both Aharonov–Bohm and Berry phases, generating chiral spin interactions that can stabilize a chiral spin liquid. I will then explore more exotic crystals in which the constituent particles are abelian or non-Abelian anyons. Such “anyon crystals” naturally appear near commensurate fillings of fractional quantum Hall states and fractional Chern insulators, and modify thermodynamic and transport properties of the condensate in an interesting way.