Matthew O'Brien, University of Illinois, Urbana-Champaign

Quantum dynamics of 2D randomly pinned charge density waves

The nature of dynamic charge correlations in randomly pinned charge density waves (CDW) is a long-standing theoretical problem. The inherent disorder present in real materials and the particular fragility of charge order to impurities makes this problem especially relevant to a host of systems currently at the forefront of modern condensed matter physics, including the cuprate high temperature superconductors and transition metal dichalcogenides. To address this question, we build on an exactly-solvable model of a 2D randomly pinned incommensurate CDW first introduced by us, and use the large-N technique to determine the phase diagram and CDW correlations. Our approach considers quantum and thermal fluctuations and disorder on equal footing by treating all effects non-perturbatively. We reveal a novel crossover between under-damped and over-damped dynamics of the fluctuations of the CDW order.