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Light helicity detector based on 2D magnetic semiconductor CrI₃.

ABSTRACT: Two-dimensional magnetic semiconductors provide a platform for studying physical phenomena at atomically thin limit, and promise magneto-optoelectronic devices application. Here, we report light helicity detectors based on graphene-CrI₃-graphene vdW heterostructures. We investigate the circularly polarized light excited current and reflective magnetic circular dichroism (RMCD) under various magnetic fields in both monolayer and multilayer CrI₃ devices. The devices exhibit clear helicity-selective photoresponse behavior determined by the magnetic state of CrI₃. We also find abnormal negative photocurrents at higher bias in both monolayer and multilayer CrI₃. A possible explanation is proposed for this phenomenon. Our work reveals the interplay between magnetic and optoelectronic properties in CrI₃ and paves the way to developing spin-optoelectronic devices.

SUBMITTER: Cheng X

PROVIDER: S-EPMC8617301 | biostudies-literature |

REPOSITORIES: biostudies-literature

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