Photon lattices

The arrival of CRCN Alberto Amo in 2017 opened a new line of research in topological photonics. The main goal is to study novel topological phases in lattices of photonic resonators. One of the preferred photonic systems of the group to address this physics is lattices of coupled micropillars in which the dynamics of light can be described using a driven-dissipative Schrödinger equation in the tight binding limit. Among the most important achievements, the group has reported the observation of novel types of Dirac cone dispersions (M. Milicevic PRX 9, 31010 (2019)), the first measurement of the topological invariants associated to a honeycomb lattice (P. St-Jean et al., PRL 126, 127403 (2021)), the observation of Landau levels for photons and helical edge states (O. Jamadi et al., LSA 9, 144 (2020)) and of dissipative solitons in a topological gap (N. Pernet et al., Nat. Phys. 18, 678 (2022)).

In 2020 the group was awarded an ERC Consolidator grant (EmergenTopo) to pursue these goals. Within this project we developed a new experimental set-up based on two coupled fibre rings that allows implementing physics of lattices subject to time modulations. Thanks to this set-up we have been the first to experimentally unveil a novel topological phase known as “extrinsic topology”, which is exclusive to systems subject to discrete-step evolution (Adiyatullin et al., PRL 130, 056901 (2023), El Sokhen et al., arXiv:2311.10619).

The topological photonics activity of the group has allowed a structuration of this research area at the University of Lille beyond the PhLAM laboratory. Within the activities of the Labex CEMPI, a workgroup on “topology and matter” co-chaired by Alberto Amo organises regular seminars and discussions with members of the mathematics Laboratory Paul Painlevé and of the micro and nanotechnology institute IEMN. With the latter, a scientific collaboration has been established to develop topological photonic crystal devices for THz technologies (G. Lévêcque et al., PRA 108, 043505 (2023)).

The topological photonics activity has a strong international visibility as attested by the invitation to write 3 review articles on the subject (including T. Ozawa et al., RMP 91, 15006 (2019)), the co-organisation of 5 international workshops and conferences on the topic since 2018, and 31 invited talks at international conferences and workshops in the period 2018-2023.

Another important activity of the OES group is the implementation of a new experimental technique to measure single shot images of the optical field emitted by polaritons in a microcavity with a time resolution of 1ps. This technique is unique in the world, and it will allow studying turbulent phenomena in polariton superfluids and spontaneous symmetry breaking associated to quantum and classical phase transitions of photon gases. A first publication is under preparation.

The development of this technique has been possible thanks to the synergy between the know-how on polariton superfluidity of the group of Alberto Amo and the strong experience in optical sampling techniques of a number of members of the OES group including Pierre Suret. Since 2023, a freshly recruited CRCN (Clément Hainaut), is fully devoted to this experiment and its extensions to measure quantum correlations of photon gases.

Discover the latest scientific activities in photon lattices and fluids of light at PhotonLattices.eu.