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Title: Spin-correlated exciton–polaritons in a van der Waals magnet
Strong coupling between light and elementary excitations is emerging as a powerful tool to engineer the properties of solid-state systems. Spin-correlated excitations that couple strongly to optical cavities promise control over collective quantum phenomena such as magnetic phase transitions, but their suitable electronic resonances are yet to be found. Here, we report strong light–matter coupling in NiPS3, a van der Waals antiferromagnet with highly correlated electronic degrees of freedom. A previously unobserved class of polaritonic quasiparticles emerges from the strong coupling between its spin-correlated excitons and the photons inside a microcavity. Detailed spectroscopic analysis in conjunction with a microscopic theory provides unique insights into the origin and interactions of these exotic magnetically coupled excitations. Our work introduces van der Waals magnets to the field of strong light–matter physics and provides a path towards the design and control of correlated electron systems via cavity quantum electrodynamics.  more » « less
Award ID(s):
1936276 2112550
PAR ID:
10356038
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Nature Nanotechnology
ISSN:
1748-3387
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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