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Multiwavelength magnetic coding of helical luminescence in ferromagnetic 2D layered CrI₃.

ABSTRACT: Two-dimensional (2D) van der Waals (vdW) ferromagnets have opened new avenues for manipulating spin at the limits of single or few atomic layers, and for creating unique magneto-exciton devices through the coupling of ferromagnetic (FM) orders and excitons. However, 2D vdW ferromagnets explored so far have rarely possessed exciton behaviors; to date, FM CrI₃ have been revealed to show ligand-field photoluminescence correlated with FM ordering, but typically with a broad emission peak. Here, we report a straightforward approach to realize strong coupling of narrow helical emission and FM orders in CrI₃ through microsphere cavity. The resonant whispering-gallery modes (WGM) of SiO₂ microspheres cause strong oscillation helical emissions with a full width at half-maximum (FWHM) of ∼5 nm under continuous wave excitation. Reversible magnetic coding of helical luminescence is realized in the range of 950-1100 nm. This work enables numerous opportunities for creating magnetic encoding lasing for photonic integrated chips.

SUBMITTER: Peng B

PROVIDER: S-EPMC8718829 | biostudies-literature |

REPOSITORIES: biostudies-literature

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