Surface-modified Wannier-Stark states in a 1D optical lattice

TL;DR

This paper investigates the energy spectrum of atoms in a 1D optical lattice near a surface, introducing a comprehensive model that combines Casimir-Polder and Lennard-Jones potentials to reveal complex atomic states.

Contribution

It presents a new effective model for atom-surface interactions in optical lattices, capturing both long-range and short-range effects non-perturbatively.

Findings

Identification of surface-localized loosely-bound states

Discovery of a modified Wannier-Stark ladder near the surface

Proposal of atomic interferometry to study atom-surface interactions

Abstract

We study the energy spectrum of atoms trapped in a vertical 1D optical lattice in close proximity to a reflective surface. We propose an effective model to describe the interaction between the atoms and the surface at any distance. Our model includes the long-range Casimir-Polder potential together with a short-range Lennard-Jones potential, which are considered non-perturbatively with respect to the optical lattice potential. We find an intricate energy spectrum which contains a pair of loosely-bound states localized close to the surface in addition to a surface-modified Wannier-Stark ladder at long distances. Atomic interferometry involving those loosely-bound atom-surface states is proposed to probe the adsorption dynamics of atoms on mirrors.