近日，北京大学张青团队报道了范德华CrSBr的腔增强巨磁光线性二色性。2026年3月2日出版的《美国化学会志》发表了这项成果。

利用范德瓦尔斯CrSBr晶体构建的准一维激子-极化激元光学腔平台，研究组实现了覆盖可见光到近红外波段的稳健且可重构的磁光二色性。该平台展现出强且多参数可调的的面内线性二色性，可响应磁场、温度和晶体厚度变化。

激子-光子耦合的各向异性是产生这种优越且可调面内各向异性的根源，并通过光学腔得到增强。研究组进一步展示了在CrSBr微腔中，各向异性诱导的光学自旋-轨道耦合对左旋和右旋圆偏振分量的有效调制。这些结果为开发适用于光子学、量子技术和光电子学应用的紧凑型隔离器、调制器和偏振器提供了重要参考。

附：英文原文

Title: Cavity-Enhanced Giant Magneto-Optical Linear Dichroism in van der Waals CrSBr

Author: Kwok Kwan Tang, Chun Li, Xuekai Ma, Jiaqi Guo, Xinyi Deng, Tian Lan, Qinglin Jia, Yuyang Zhang, Changhai Zhu, Xinfeng Liu, Chao Shen, Handong Sun, Qing Zhang

Issue&Volume: March 2, 2026

Abstract: Compact magneto-optical dichroism devices facilitate active and dynamic manipulation of photons at the chip scale, making them a key focus in the development of integrated photonic and optoelectronic systems. However, the performance of existing optical anisotropy materials is often constrained by their narrow operational bandwidth and temperature and insufficient magnetically induced tunability. Herein, we demonstrate robust and reconfigurable magneto-optical dichroism spanning the visible to near-infrared spectrum using a quasi-1D exciton–polariton cavity platform constructed from van der Waals CrSBr crystals. The platform demonstrates strong and multiparameter-tunable in-plane linear dichroism, responsive to magnetic field, temperature, and crystal thickness variations. The anisotropy in exciton–photon coupling is the origin of the superior and tunable in-plane anisotropy, which is enhanced by the optical cavity. We further demonstrate the effective modulation of the left- and right-circularly polarized components in anisotropy-induced optical spin–orbit coupling in CrSBr microcavities. These results offer valuable insights for the development of compact isolators, modulators, and polarizers for photonic, quantum, and optoelectronic applications.

DOI: 10.1021/jacs.5c19443

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.5c19443