4 p.m. - 5 p.m. Location: SLC 1.102
Dr. Inti Sodemann (MIT)
Fractionalization in quantum matter: past, present and future
Up until a few decades ago we used to believe that the low energy excitations in any phase of matter could be understood either as dressed versions of the bare electron or as bosonic collective modes like sound waves. Toward the end of the 20th century, however, a lucky combination of experimental discoveries and theoretical insights shattered these expectations, and made clear that stable particle-like excitations can exist that behave like fractions of the bare electron. A highly successful recipe for achieving these fractionalized phases experimentally is to subject a two dimensional electron liquid to a large magnetic field thus reaching the so-called fractional quantum Hall regime. In this talk I will describe a few selected recent developments in our understanding and realization of these exotic phases. In particular, I will explain how electrons in graphene exhibit a rich structure of fractionalized phases coexisting with complex symmetry breaking patterns. I will also describe our recent elucidation of a remarkable connection between two venerable exotic quantum Hall liquids: the composite fermi liquid and the Bose-Einstein condensate of excitons realized in quantum Hall bilayers. I will close with some thoughts on the future of fractionalization and its potential realization outside the realms of quantum Hall and frustrated magnets.