June 3rd
when: Wednesday 03/06/2020, 14:00
where: Zoom Meeting, invitation sent by mail
speaker: Debanjan Chowdurry (Cornell University)
title: Deconfined metallic quantum criticality
abstract:
A number of strongly correlated electronic materials exhibit quantum criticality that does not fit into the conentional Landau-Ginzburg-Wilson paradigm of continuous phase transitions. Inspired by these experimental examples, I will discuss a new class of quantum phase transitions that describe a continuous transition between a gapless Fermi liquid metal with a generic electron Fermisurface and gapped electrical insulatoors. Such phase transitions are described in terms of a finite density of fractionalized quasiparticles ("partons") coupled to emergent gauge fields. I will discuss various concrete examples of such gauge theories and describe their associated phase transtitions using a renormalization group framework. Remarkably, we find examples of continuous phase transitions between Landau Fermi liquid metals and gapped insulatiors, where the quantum critical point hosts a non-fermi liquid with a sharp Fermi surface but no long-lived quasiiparticles. I will comment on the relevance of this new theoretical framework for some of the most pressing questions in the field of quantum matter.