000165009 001__ 165009 000165009 005__ 20251204150238.0 000165009 0247_ $$2doi$$a10.1038/s41567-022-01565-4 000165009 0248_ $$2sideral$$a146445 000165009 037__ $$aART-2022-146445 000165009 041__ $$aeng 000165009 100__ $$aKwon, Joonhyuk 000165009 245__ $$aFormation of matter-wave polaritons in an optical lattice 000165009 260__ $$c2022 000165009 5203_ $$aThe polariton—a quasiparticle formed by the strong coupling of a photon to a matter excitation—is a fundamental ingredient of emergent photonic quantum systems ranging from semiconductor nanophotonics to circuit quantum electrodynamics. Exploiting the interaction between polaritons has led to the realization of superfluids of light as well as of strongly correlated phases in the microwave domain, with similar efforts underway for microcavity excitons–polaritons. Here we develop an ultracold-atom analogue of an exciton–polariton system in which interacting polaritonic phases can be studied with full tunability and in the absence of dissipation. In our optical lattice system, the exciton is replaced by an atomic excitation, whereas an atomic matter wave is substituted for the photon under a strong dynamical coupling between the two constituents that hybridizes the two dispersion relations. We spectroscopically access the band structure of the matter-wave polariton by coupling the upper and lower polariton branches, as well as explore polaritonic transport in the superfluid and Mott-insulating regimes, finding quantitative agreement with our theoretical expectations. Our work sheds light on fundamental polariton properties and related many-body phenomena, and opens up novel possibilities for studies of polaritonic quantum matter. 000165009 540__ $$9info:eu-repo/semantics/closedAccess$$aAll rights reserved$$uhttp://www.europeana.eu/rights/rr-f/ 000165009 590__ $$a19.5$$b2022 000165009 591__ $$aPHYSICS, MULTIDISCIPLINARY$$b4 / 85 = 0.047$$c2022$$dQ1$$eT1 000165009 592__ $$a7.955$$b2022 000165009 593__ $$aPhysics and Astronomy (miscellaneous)$$c2022$$dQ1 000165009 594__ $$a28.0$$b2022 000165009 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion 000165009 700__ $$aKim, Youngshin 000165009 700__ $$0(orcid)0000-0001-7049-0250$$aLanuza, Alfonso 000165009 700__ $$aSchneble, Dominik 000165009 773__ $$g18, 6 (2022), 657-661$$pNat. Phys.$$tNature Physics$$x1745-2473 000165009 8564_ $$s8236721$$uhttps://zaguan.unizar.es/record/165009/files/texto_completo.pdf$$yVersión publicada 000165009 8564_ $$s2261181$$uhttps://zaguan.unizar.es/record/165009/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada 000165009 909CO $$ooai:zaguan.unizar.es:165009$$particulos$$pdriver 000165009 951__ $$a2025-12-04-14:39:14 000165009 980__ $$aARTICLE