Description

Place: Seminar room, Theoretical Physics

Time: 12:00

Speaker: Ravi Chhajlany ( ICFO-Institut de Ciències Fotòniques and Adam Mickiewicz University)

Title: Hidden order in a 1-d model of interacting fermions with extended correlated hopping

Abstract:

The field of ultra-cold gases in optical lattices is  enabling the simulation of various well known quantum many body models underlying complex collective phenomena. Vice versa, possible optical lattice setups themselves naturally motivate the study of new, interesting models beyond traditional condensed matter physics.

Here we consider a problem of the latter type. We introduce the basic model describing the physics of mixtures of two-species of neutral ultra-cold fermions loaded onto a spin-dependent bipartite 1-dimensional lattice. Sophisticated single particle experiments using separated spin-dependent lattices have already been reported recently in the literature. We elucidate here the many-body aspects, hitherto unstudied – to our knowledge, that may be attained  in  dynamically modulated lattices of this type. We discuss how apart from familiar hopping and interaction terms, the model has a natural strong correlated hopping amplitude. We  provide a complete characterization of the properties of the system using a combination of a novel analytical solution and numerical methods. In summary, we predict that two main phases are  realized in the system  - (i) a surprising phase with both hidden long range string order and critical hole superconducting correlations, and (ii) a ferromagnetic phase of itinerant particles.