講師：Inti Sodemann (Massachusetts Institute of Technology)
題目：Particle-hole symmetric phases in multicomponent Landau levels
概要：The picture of fractional quantum Hall states as liquids of composite particles made from electrons bound to fluxes has evolved over the years as a central paradigm in the understanding of these phases. A recent proposal on the compressible phase that arises in half-filled Landau levels allows to consistently incorporate the particle-hole symmetry by viewing the composite fermion as a Dirac particle. In turn, the natural habitat for this Dirac composite fermion is the surface of a chiral topological insulator protected by an anti-unitary particle-hole symmetry with a single Dirac cone. In this talk I will describe generalizations of these ideas to the case of N-component landau levels, such as those arising in quantum Hall bilayers (N=2) and graphene (N=4). When multi-component Landau levels are half filled they can be viewed as the surface of a chiral topological insulator with N Dirac cones. I will describe gapped phases that respect the particle-hole symmetry and are top
ologically ordered and discuss their potential experimental realization.