Cold atoms talk

Speaker: Callum Duncan, M.Sc. Heriot-Watt University, UK.

Title: Many-Body Localization in Strongly Correlated One-Dimensional Systems with CONAN

Abstract:

Many-body localization is the disorder induced localization of interacting particles, which is contrary to the usual case of conventional thermodynamics of thermalization. The field of many-body localization has been one that has developed major interest over recent years, with work being conducted on the theory of the localized-delocalized phase transition and the observation of many-body localization for fermions in a quasirandom optical lattice in Munich last year. Most of what has been studied to date has been considering localization of particles (or formally their charge). Here I will present our first preliminary results regarding the possibility and nature of the localisation or absence thereof of the spin degrees of freedom in a spin-charge separated system consisting of strongly-interacting one-dimensional atoms in a quasirandom lattice. To investigate this we use the recently released CONAN code, which has been developed by Zinner's group here in Aarhus. Using the property that strongly correlated system of particles with zero-range interactions can be mapped onto a spin chain, CONAN calculates the exchange coefficients of such a system for an arbitrary external potential. By inducing a degree of disorder into the systems potential, we can access the many-body localisation regime for the charge degrees of freedom. By then mapping this to the spin chain model and using CONAN it is possible to investigate the localisation properties of the spin. I will also discuss different wave function implementations for CONAN that are more suitable for the problem at hand.