---
abstract: 'The latest advances in the field of photonics have enabled the simulation of an increasing number of quantum models in photonic systems, turning them into an important tool for realizing exotic quantum phenomena. In this paper we suggest different ways in which these systems can be used to study the interplay between flat band dynamics, topology and interactions in a well-known quasi-1D topological insulator: the Creutz ladder. Firstly, a simple experimental protocol is proposed to observe the Aharonov-Bohm localization in the noninteracting system, and the different experimental setups that might be used for this are reviewed. We then consider the inclusion of a repulsive Hubbard-type interaction term, which can give rise to repulsively bound pairs termed doublons. The dynamics of these quasiparticles are studied for different points of the phase diagram, including a regime in which pairs are localized and particles are free to move. Finally, a scheme for the photonic implementation of a two-particle bosonic Creutz-Hubbard model is presented.'
author:
- 'J. Zurita'
- 'C.E. Creffield'
- 'G. Platero'
bibliography:
- 'Refs\_brief.bib'
title: 'Topology and interactions: using photonic systems as quantum simulators'
---

We would like to thank M. A. Martín-Delgado and A. Bermúdez for fruitful discussions. CEC was supported by Spain’s MINECO through Grant No. FIS2017-84368-P. GP was supported by Spain’s MINECO through Grant No. MAT2017- 86717-P and by CSIC Research Platform PTI-001.
