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Title: Dispersive Dark Excitons in van der Waals Ferromagnet CrI3
Spin-flip dark excitons are optical-dipole-forbidden quasiparticles with remarkable potential in optoelectronics, especially when they are realized within cleavable van der Waals materials. Despite this potential, dark excitons have not yet been definitively identified in ferromagnetic van der Waals materials. Here, we report two dark excitons in a model ferromagnetic material CrI3 using high-resolution resonant inelastic x-ray scattering and show that they feature narrower linewidths compared to the bright excitons previously reported in this material. These excitons are shown to have spin-flip character, to disperse as a function of momentum, and to change through the ferromagnetic transition temperature. Given the versatility of van der Waals materials, these excitons hold promise for new types of magneto-optical functionality.  more » « less
Award ID(s):
2441874
PAR ID:
10657270
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
American Physical Society (APS)
Date Published:
Journal Name:
Physical Review X
Volume:
15
Issue:
1
ISSN:
2160-3308
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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