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Twist Engineering of Anisotropic Excitonic and Optical Properties of a Two-Dimensional Magnetic Semiconductor

Li, Qiuyang [University of Michigan] (ORCID:0000000281923960)·Wan, Xiaohan [University of Michigan]·Li, Senlei [Georgia Institute of Technology]·Alfrey, Adam [University of Michigan] (ORCID:0000000340798726)·Liu, Wenhao [The University of Texas at Dallas]·Zhai, Zixin [The University of Texas at Dallas] (ORCID:0000000227208085)·Alpers, Wyatt [University of Michigan] (ORCID:0009000673570321)·Yang, Yujie [University of Michigan] (ORCID:0009000686635796)·Wladyszewska, Irmina [University of Michigan] (ORCID:0009000825007088)·Beach, Christiano W. [University of Michigan]·Zhao, Liuyan [University of Michigan]·Lv, Bing [The University of Texas at Dallas] (ORCID:0000000294915177)·Du, Chunhui Rita [Georgia Institute of Technology] (ORCID:0000000180637711)·Sun, Kai [University of Michigan] (ORCID:0000000195957646)·Deng, Hui [University of Michigan; University of Michigan] (ORCID:0000000306293230)
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Abstract

Two-dimensional (2D) van der Waals (vdW) magnetic semiconductors are a new class of quantum materials for studying the emergent physics of excitons and spins in the 2D limit. Twist engineering provides a powerful tool to manipulate the fundamental properties of 2D vdW materials. Here, in this work, we show that twist engineering of the anisotropic ferromagnetic monolayer semiconductor CrSBr leads to bilayer magnetic semiconductors with continuously tunable magnetic moment, dielectric anisotropy, exciton energy, and linear dichroism. We furthermore provide a model for exciton energy in the media with tunable anisotropy. These results advance fundamental studies of 2D vdW materials and open doors to applications to nano-optics, twistronics, and spintronics.

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36 MATERIALS SCIENCE75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYtwo-dimensional magnet, moire magnet, linear optics

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Li, Qiuyang [University of Michigan] (ORCID:0000000281923960), Wan, Xiaohan [University of Michigan], Li, Senlei [Georgia Institute of Technology], Alfrey, Adam [University of Michigan] (ORCID:0000000340798726), Liu, Wenhao [The University of Texas at Dallas], Zhai, Zixin [The University of Texas at Dallas] (ORCID:0000000227208085), Alpers, Wyatt [University of Michigan] (ORCID:0009000673570321), Yang, Yujie [University of Michigan] (ORCID:0009000686635796), Wladyszewska, Irmina [University of Michigan] (ORCID:0009000825007088), Beach, Christiano W. [University of Michigan], Zhao, Liuyan [University of Michigan], Lv, Bing [The University of Texas at Dallas] (ORCID:0000000294915177), Du, Chunhui Rita [Georgia Institute of Technology] (ORCID:0000000180637711), Sun, Kai [University of Michigan] (ORCID:0000000195957646), Deng, Hui [University of Michigan; University of Michigan] (ORCID:0000000306293230). 2025-10-06. Twist Engineering of Anisotropic Excitonic and Optical Properties of a Two-Dimensional Magnetic Semiconductor. https://doi.org/10.1103/zbbr-5mgv

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36 MATERIALS SCIENCE subject75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY subjecttwo-dimensional magnet, moire magnet, linear optics subject

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