We present a comprehensive investigation of optical properties in MoSe2/CrSBr heterostructures, unveiling the presence of localized excitons represented by a new emission feature, X∗. We demonstrate through temperature- and power-dependent photoluminescence spectroscopy that X∗ originates from excitons confined by intrinsic defects within the CrSBr layer. The valley polarization of X∗ and trion peaks displays opposite polarity under a magnetic field, which closely correlates with the magnetic order of CrSBr. This is attributed to spin-dependent charge transfer mechanisms across the heterointerface, supported by density functional theory calculations revealing a type-II band alignment and spin-polarized band structures. Furthermore, the strong in-plane anisotropy of CrSBr induces unique polarization-dependent responses in MoSe2 emissions. Our study highlights the crucial role of defects in shaping excitonic properties. It offers valuable insights into spectral-resolved proximity effects in van der Waals heterostructures between semiconductor and magnet, contributing to advancing spintronic and valleytronic devices.
@article{arxiv.2405.16079,
title = {Intrinsic localized excitons in MoSe$_2$/CrSBr heterostructures},
author = {Xinyue Huang and Zhigang Song and Yuchen Gao and Pingfan Gu and Kenji Watanabe and Takashi Taniguchi and Shiqi Yang and Zuxin Chen and Yu Ye},
journal= {arXiv preprint arXiv:2405.16079},
year = {2024}
}