title: Bosonic Condensation and Disorder-Induced Localization in a Flat Band.
abstract: We report on the engineering of a nondispersive (flat) energy band in a geometrically frustrated lattice of micropillar optical cavities. By taking advantage of the non-Hermitian nature of our system, we achieve bosonic condensation of exciton polaritons into the flat band. Because of the infinite effective mass in such a band, the condensate is highly sensitive to disorder and fragments into localized modes reflecting the elementary eigenstates produced by geometric frustration. This realization offers a novel approach to studying coherent phases of light and matter under the controlled interplay of frustration, interactions, and dissipation.
authors.affiliation: Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France.
authors.forename: F
authors.initials: F
authors.lastname: Baboux
authors.affiliation: Department of Engineering Science and Physics, College of Staten Island, CUNY, New York 10314, USA.|The Graduate Center, CUNY, New York 10016, USA.
authors.forename: L
authors.initials: L
authors.lastname: Ge
authors.affiliation: Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France.
authors.forename: T
authors.initials: T
authors.lastname: Jacqmin
authors.affiliation: Institute for Theoretical Physics, ETH Zurich, 8093 Zurich, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Biondi
authors.affiliation: Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France.
authors.forename: E
authors.initials: E
authors.lastname: Galopin
authors.affiliation: Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France.
authors.forename: A
authors.initials: A
authors.lastname: Lemaître
authors.affiliation: Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France.
authors.forename: L
authors.initials: L
authors.lastname: Le Gratiet
authors.affiliation: Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France.
authors.forename: I
authors.initials: I
authors.lastname: Sagnes
authors.affiliation: Institute for Theoretical Physics, ETH Zurich, 8093 Zurich, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Schmidt
authors.affiliation: Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: H E
authors.initials: HE
authors.lastname: Türeci
authors.affiliation: Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France.
authors.forename: A
authors.initials: A
authors.lastname: Amo
authors.affiliation: Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France.|Physics Deparment, Ecole Polytechnique, Université Paris-Saclay, F-91128 Palaiseau Cedex, France.
authors.forename: J
authors.initials: J
authors.lastname: Bloch