# Staggered Ground States in an Optical Lattice

## TL;DR

This paper investigates complex ground states in a one-dimensional optical lattice with long-range interactions, revealing new staggered phases and potential links to twisted superfluids using a mean-field Gutzwiller approach.

## Contribution

It introduces a mean-field analysis of long-range interacting Bose gases, discovering novel staggered phases and connecting them to previously known twisted superfluids.

## Key findings

- Identification of density wave and supersolid phases due to long-range interactions
- Discovery of new staggered phases with two-site periodic density and transport properties
- Observation of unconventional phases with sign staggered order parameters

## Abstract

Non-standard Bose-Hubbard models can exhibit rich ground state phase diagrams, even when considering the one-dimensional limit. Using a self-consistent Gutzwiller diagonalisation approach, we study the mean-field ground state properties of a long-range interacting atomic gas in a one-dimensional optical lattice. We first confirm that the inclusion of long-range two-body interactions to the standard Bose-Hubbard model introduces density wave and supersolid phases. However, the introduction of pair and density-dependent tunnelling can result in new phases with two-site periodic density, single-particle transport and two-body transport order parameters. These staggered phases are potentially a mean-field signature of the known novel twisted superfluids found via a DMRG approach [PRA \textbf{94}, 011603(R) (2016)]. We also observe other unconventional phases, which are characterised by sign staggered order parameters between adjacent lattice sites.