Excitons are fundamental excitations that govern the optical properties of semiconductors. Interactions between excitons can lead to various emergent phases of matter and large nonlinear optical responses. In most semiconductors, excitons interact via exchange interactions or phase-space filling. Correlated materials that host excitons coupled to other degrees of freedom could offer pathways for controlling these interactions. Here we demonstrate magnon-mediated interactions between excitons in CrSBr, an antiferromagnetic semiconductor. These interactions manifest as the dependence of the exciton energy on the exciton density via a magnonic adjustment of the spin canting angle. Our study demonstrates the emergence of quasiparticle-mediated interactions in correlated quantum materials, leading to large nonlinear optical responses and potential device concepts such as magnon-mediated quantum transducers.

CREOL The College of Optics and Photonics University of Central Florida Orlando FL USA

Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center Universidad Autónoma de Madrid Madrid Spain

Department of Electrical Engineering The City College of New York New York NY USA

Department of Inorganic Chemistry University of Chemistry and Technology Prague Prague Czech Republic

Department of Physics and Research Center OPTIMAS Rheinland Pfälzische Technische Universität Kaiserslautern Landau Kaiserslautern Germany

Department of Physics City College of New York New York NY USA

Department of Physics Graduate Center of the City University of New York New York NY USA

Materials Science Center National Renewable Energy Laboratory Golden CO USA

Photonics Initiative CUNY Advanced Science Research Center New York NY USA

Theory and Simulation of Condensed Matter King's College London London UK

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Johansen, Ø., Kamra, A., Ulloa, C., Brataas, A. & Duine, R. A. Magnon-mediated indirect exciton condensation through antiferromagnetic insulators. Phys. Rev. Lett. 123, 167203 (2019). PubMed

Regan, E. C. et al. Emerging exciton physics in transition metal dichalcogenide heterobilayers. Nat. Rev. Mater. 7, 778–795 (2022).

Snoke, D. Spontaneous Bose coherence of excitons and polaritons. Science 298, 1368–1372 (2002). PubMed

Wang, Z. et al. Evidence of high-temperature exciton condensation in two-dimensional atomic double layers. Nature 574, 76–80 (2019). PubMed

Deng, H., Weihs, G., Santori, C., Bloch, J. & Yamamoto, Y. Condensation of semiconductor microcavity exciton polaritons. Science 298, 199–202 (2002). PubMed

Kasprzak, J. et al. Bose–Einstein condensation of exciton polaritons. Nature 443, 409–414 (2006). PubMed

Amo, A. et al. Superfluidity of polaritons in semiconductor microcavities. Nat. Phys. 5, 805–810 (2009).

Li, J. I. A., Taniguchi, T., Watanabe, K., Hone, J. & Dean, C. R. Excitonic superfluid phase in double bilayer graphene. Nat. Phys. 13, 751–755 (2017).

Jérome, D., Rice, T. M. & Kohn, W. Excitonic insulator. Phys. Rev. 158, 462–475 (1967).

Cercellier, H. et al. Evidence for an excitonic insulator phase in 1T-TiSe PubMed

Kogar, A. et al. Signatures of exciton condensation in a transition metal dichalcogenide. Science 358, 1314–1317 (2017). PubMed

Joglekar, Y. N., Balatsky, A. V. & Das Sarma, S. Wigner supersolid of excitons in electron–hole bilayers. Phys. Rev. B 74, 233302 (2006).

Axt, V. M. & Mukamel, S. Nonlinear optics of semiconductor and molecular nanostructures; a common perspective. Rev. Mod. Phys. 70, 145–174 (1998).

Li, W., Lu, X., Dubey, S., Devenica, L. & Srivastava, A. Dipolar interactions between localized interlayer excitons in van der Waals heterostructures. Nat. Mater. 19, 624–629 (2020). PubMed

Yazdani, N. et al. Coupling to octahedral tilts in halide perovskite nanocrystals induces phonon-mediated attractive interactions between excitons. Nat. Phys. 20, 47–53 (2024). PubMed

Wilson, N. P. et al. Interlayer electronic coupling on demand in a 2D magnetic semiconductor. Nat. Mater. 20, 1657–1662 (2021). PubMed

Bae, Y. J. et al. Exciton-coupled coherent magnons in a 2D semiconductor. Nature 609, 282–286 (2022). PubMed

Diederich, G. M. et al. Tunable interaction between excitons and hybridized magnons in a layered semiconductor. Nat. Nanotechnol. 18, 23–28 (2023). PubMed

Dirnberger, F. et al. Magneto-optics in a van der Waals magnet tuned by self-hybridized polaritons. Nature 620, 533–537 (2023). PubMed

Brennan, N. J., Noble, C. A., Tang, J., Ziebel, M. E. & Bae, Y. J. Important elements of spin–exciton and magnon–exciton coupling. ACS Phys. Chem. Au 4, 322–327 (2024). PubMed PMC

Telford, E. J. et al. Layered antiferromagnetism induces large negative magnetoresistance in the van der Waals semiconductor CrSBr. Adv. Mater. 32, 2003240 (2020).

Wang, H., Qi, J. & Qian, X. Electrically-tunable high Curie temperature two-dimensional ferromagnetism in van der Waals layered crystals. Appl. Phys. Lett. 117, 083102 (2020).

Lee, K. et al. Magnetic order and symmetry in the 2D semiconductor CrSBr. Nano Lett. 21, 3511–3517 (2021). PubMed

Scheie, A. et al. Spin waves and magnetic exchange Hamiltonian in CrSBr. Adv. Sci. 9, 2202467 (2022).

Klein, J. et al. Sensing the local magnetic environment through optically active defects in a layered magnetic semiconductor. ACS Nano 17, 288–299 (2023). PubMed

Bianchi, M. et al. Paramagnetic electronic structure of CrSBr: comparison between ab initio GW theory and angle-resolved photoemission spectroscopy. Phys. Rev. B 107, 235107 (2023).

Watson, M. D. et al. Giant exchange splitting in the electronic structure of A-type 2D antiferromagnet CrSBr. npj 2D Mater. Appl. 8, 54 (2024).

Shao, Y. et al. Magnetically confined surface and bulk excitons in a layered antiferromagnet. Nat. Mater. 24, 391–398 (2025). PubMed

Wang, T. et al. Magnetically-dressed CrSBr exciton-polaritons in ultrastrong coupling regime. Nat. Commun. 14, 5966 (2023). PubMed PMC

Sun, Y. et al. Dipolar spin wave packet transport in a van der Waals antiferromagnet. Nat. Phys. 20, 794–800 (2024).

Guo, Y., Zhang, Y., Yuan, S., Wang, B. & Wang, J. Chromium sulfide halide monolayers: intrinsic ferromagnetic semiconductors with large spin polarization and high carrier mobility. Nanoscale 10, 18036–18042 (2018). PubMed

Klein, J. et al. The bulk van der Waals layered magnet CrSBr is a quasi-1D material. ACS Nano 17, 5316–5328 (2023). PubMed

Lin, K. et al. Strong exciton–phonon coupling as a fingerprint of magnetic ordering in van der Waals layered CrSBr. ACS Nano 18, 2898–2905 (2024). PubMed PMC

Datta, B. et al. Highly nonlinear dipolar exciton-polaritons in bilayer MoS PubMed PMC

Louca, C. et al. Interspecies exciton interactions lead to enhanced nonlinearity of dipolar excitons and polaritons in MoS PubMed PMC

Cunningham, B., Grüning, M., Pashov, D. & van Schilfgaarde, M. QS GŴ: quasiparticle self consistent GW with ladder diagrams in W. Phys. Rev. B 108, 165104 (2023).

van Schilfgaarde, M., Kotani, T. & Faleev, S. Quasiparticle self-consistent GW theory. Phys. Rev. Lett. 96, 226402 (2006). PubMed

Pashov, D. et al. Questaal: a package of electronic structure methods based on the linear muffin-tin orbital technique. Comput. Phys. Commun. 249, 107065 (2020).

Chaves, A. & Peeters, F. M. Tunable effective masses of magneto-excitons in two-dimensional materials. Solid State Commun. 334–335, 114371 (2021).

Zipfel, J. et al. Spatial extent of the excited exciton states in WS

Pacuski, W. et al. Excitonic giant Zeeman effect in wide gap diluted magnetic semiconductors based on ZnO and GaN. Acta Phys. Pol. A 110, 303–309 (2006).

Klein, J. et al. Control of structure and spin texture in the van der Waals layered magnet CrSBr. Nat. Commun. 13, 5420 (2022). PubMed PMC

Hall, S. J., Budden, P. J., Zats, A. & Sfeir, M. Y. Optimizing the sensitivity of high repetition rate broadband transient optical spectroscopy with modified shot-to-shot detection. Rev. Sci. Instrum. 94, 043005 (2023). PubMed

Magnetic Correlation Spectroscopy in CrSBr