Negative Refraction of Excitations in the Bose-Hubbard Model

TL;DR

This paper demonstrates that by spatially varying interactions in a Bose-Hubbard system, one can control excitation trajectories, including negative refraction, enabling novel optical-like manipulation of quantum excitations.

Contribution

It introduces a method to engineer negative refraction of excitations in the Bose-Hubbard model through spatially varying onsite interactions.

Findings

Negative refraction of excitations demonstrated

Potential to create flat lenses for quantum excitations

Control over excitation trajectories achieved

Abstract

Ultracold atoms in optical lattices provide a unique opportunity to study Bose- Hubbard physics. In this work we show that by considering a spatially varying onsite interaction it is possible to manipulate the motion of excitations above the Mott phase in a Bose-Hubbard system. Specifically, we show that it is possible to "engineer" regimes where excitations will negatively refract, facilitating the construction of a flat lens.