Jiang Hao, Zhang Yan, An Liheng, Tan Qinghai, Dai Xuran, Chen Yinzhu, Chen Weijin, Cai Hongbing, Fu Jintao, Zúñiga-Pérez Jesús, Li Zhiwei, Teng Jinghua, Chen Yang, Qiu Cheng-Wei, Gao Weibo
School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore.
Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore.
Nat Mater. 2025 Mar 19. doi: 10.1038/s41563-025-02155-4.
The full-range, high-sensitivity and integratable detection of circularly polarized light (CPL) is critically important for quantum information processing, advanced imaging systems and optical sensing technologies. However, mainstream CPL detectors rely on chiral absorptive materials, and thus suffer from limited response wavelengths, low responsivity and poor discrimination ratios. Here we present a chiral light detector by utilizing valley materials to observe the spin angular momentum carried by chiral light. Delicately designed centrosymmetric metamaterials that can preserve the sign of optical spin angular momentum and greatly enhance its intensity in the near field are harnessed as a medium to inject polarized electrons into valley materials, which are then detected by the valley Hall effect. This enables high-sensitivity infrared CPL detection at room temperature by valleytronic transistors, and the detection wavelength is extended to the infrared. This approach opens pathways for chiral light detection and provides insights into potential applications of valleytronics in optoelectronic sensing.
对圆偏振光（CPL）进行全范围、高灵敏度且可集成的检测，对于量子信息处理、先进成像系统和光学传感技术而言至关重要。然而，主流的CPL探测器依赖于手性吸收材料，因此存在响应波长受限、响应度低和鉴别率差等问题。在此，我们展示了一种通过利用谷材料来观测手性光所携带的自旋角动量的手性光探测器。精心设计的中心对称超材料能够保留光学自旋角动量的符号，并在近场中极大地增强其强度，以此作为一种介质将极化电子注入谷材料中，随后通过谷霍尔效应进行检测。这使得谷电子晶体管能够在室温下实现高灵敏度的红外CPL检测，并且检测波长扩展至红外波段。这种方法为手性光检测开辟了途径，并为谷电子学在光电传感中的潜在应用提供了见解。
