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Strongly correlated electron–photon systems

Abstract

An important goal of modern condensed-matter physics involves the search for states of matter with emergent properties and desirable functionalities. Although the tools for material design remain relatively limited, notable advances have been recently achieved by controlling interactions at heterointerfaces, precise alignment of low-dimensional materials and the use of extreme pressures. Here we highlight a paradigm based on controlling light–matter interactions, which provides a way to manipulate and synthesize strongly correlated quantum matter. We consider the case in which both electron–electron and electron–photon interactions are strong and give rise to a variety of phenomena. Photon-mediated superconductivity, cavity fractional quantum Hall physics and optically driven topological phenomena in low dimensions are among the frontiers discussed in this Perspective, which highlights a field that we term here ‘strongly correlated electron–photon science’.

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Acknowledgements

We thank J. Curtis for critical reading of the manuscript. V.G. was supported by NSF DMR-2037158, US-ARO contract number W911NF1310172, and the Simons Foundation. M.H. acknowledges support from AFOSR FA95502010223, FA9550-19-1-0399, ARO W911NF2010232 and ARL W911NF1920181 and the Simons Foundation. J.B. acknowledges financial support from Paris Ile-de-France Région DIM SIRTEQ, H2020-FETFLAG project PhoQus (820392), QUANTERA project Interpol (ANR-QUAN-0003-05), ANR project Quantum Fluids of Light (ANR-16-CE30-0021) and the French RENATECH network. A.R. is supported by the European Research Council (ERC-2015-AdG-694097), Grupos Consolidados (IT1249-19) and the Flatiron Institute, a division of the Simons Foundation. We acknowledge funding by the Deutsche Forschungsgemeinschaft (DFG) under Germany’s Excellence Strategy - Cluster of Excellence Advanced Imaging of Matter (AIM) EXC 2056 – 390715994 and by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) -SFB-925 - project 170620586. Support by the Max Planck Institute – New York City Center for Non-Equilibrium Quantum Phenomena.

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Bloch, J., Cavalleri, A., Galitski, V. et al. Strongly correlated electron–photon systems. Nature 606, 41–48 (2022). https://doi.org/10.1038/s41586-022-04726-w

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