Signal-to-noise issues in entanglement entropy calculations of ultracold fermions by Joaquin Drut
Mar 27, 2017 at 2:00 PM - 3:00 PMJoaquín E. Drut
University of North Carolina
Host: Prof. Simon Catterall / Contact: Yudaisy Salomón Sargentón, 315-443-5960
208 Physics Bldg.Ultracold fermions continue to be a remarkably versatile playground for quantum many-body physics. Experimentalists have exquisite control of temperature, density, coupling, and shape of the trapping potential. Additionally, a wide range of properties can be measured: from simple ones like equations of state to more involved ones like the bulk viscosity and the Rényi entanglement entropy (EE). The latter is a measure of quantum information which has received much attention due to its connection to quantum phase transitions but which has proven extremely difficult to compute: non-perturbative lattice methods for the EE display exponential signal-to-noise issues of a very similar nature as those due to a sign problem. I will outline the EE formalism, present an algorithm that solves the EE problem, and show results for strongly interacting systems in three spatial dimensions that are the first of their kind.