Colloquium – Enrico Rossi – Quantum Metric and Correlated States in Two-dimensional System

Speaker: Dr. Enrico Rossi (William and Mary)

Title: Quantum Metric and Correlated States in Two-dimensional System

Abstract:

In the past two decades some of the most interesting developments in condensed matter physics have resulted from the careful treatment of the effects of the Berry curvature in many-body systems. Exemplary is the discovery of topological insulators. The Berry curvature can be thought as the imaginary part of a complex tensor. The real part of this tensor is the quantum metric, the metric that can be used to measure the distance between quantum states belonging to a single electronic band. In this talk I will introduce the concept of quantum metric and show how it is related to properties of correlated electronic states. In particular, I will discuss how the quantum metric contributes to the superfluid density of superconductors, and exciton condensates. I will then show the importance played by the quantum metric in determining the superconducting properties of systems like twisted bilayer-graphene.