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Title: Searching for Circular Photo Galvanic Effect in Oxyhalide Perovskite Bi 4 NbO 8 Cl

The ability to reconfigure spin structure and spin‐photon interactions by an external electric field is a prerequisite for seamless integration of opto‐spintronics into modern electronics. In this study, the use of electric field on the tuning of circular photo galvanic effect in a quasi‐2D oxyhalide perovskite Bi4NbO8Cl is reported. The electrical transport measurements are applied to study the switching characteristics of the microsheet devices. The electric field is used to tune the nanoscale devices and an optical orientation approach is applied to understand the field‐tuned spin‐polarized band structures. It is found that the circular photogalvanic current can be erased and re‐created by poling, indicating the electric‐field‐based control over spin structure. The study enriches the basic understanding of the symmetry‐regulated optoelectronic response in ferroelectrics with spin‐orbit coupling.

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Award ID(s):
2039380 2005096 2031692 1916652
Author(s) / Creator(s):
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Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Functional Materials
Medium: X
Sponsoring Org:
National Science Foundation
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