Mesoscopic Aspects of Strongly Interacting Cold Atoms

TL;DR

This paper investigates the mesoscopic properties of strongly interacting cold atoms in a lattice, focusing on scattering at superfluid-Mott-insulator interfaces and their impact on heat transport.

Contribution

It introduces a scattering matrix approach to analyze quasi-particle interactions at the interface, providing new insights into thermal transport in optical lattices.

Findings

Heat conductivity is suppressed below a critical hopping value.

The formalism models transport phenomena across superfluid-Mott-insulator boundaries.

The approach aids understanding of thermalization in cold atom systems.

Abstract

Harmonically trapped lattice bosons with strong repulsive interactions exhibit a superfluid-Mott-insulator heterostructure in the form of a "wedding cake". We discuss the mesoscopic aspects of such a system within a one-dimensional scattering matrix approach and calculate the scattering properties of quasi-particles at a superfluid-Mott-insulator interface as an elementary building block to describe transport phenomena across such a boundary. We apply the formalism to determine the heat conductivity through a Mott layer, a quantity relevant to describe thermalization processes in the optical lattice setup. We identify a critical hopping below which the heat conductivity is strongly suppressed.