题目：Electrical-gain-assisted circularly polarized photodetection based on chiral plasmonic metamaterials

作者：Chenghao Chen^1,2, Zhenhai Yang^1,2,*, Tianyi Hang^1,2, Yining Hao^1,2, Yijing Chen^1,2 , Chengzhuang Zhang^1,2, Jiong Yang^1,2, Xiaoyi Liu^1,2, Xiaofeng Li^1,2,*, and Guoyang Cao^1,2,3,*

单位：

1School of Optoelectronic Science and Engineering & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China;

2 Key Laboratory of Advanced Optical Manufacturing Technologies of Jiangsu Province & Key Laboratory of Modern Optical Technologies of the Ministry of Education, Soochow University, Suzhou 215006, China;

3 Engineering Research Center of Digital Graphic and Next-Generation Printing of Jiangsu Province, Soochow University, Suzhou 215006, China;

Abstract: Circularly polarized light (CPL) detectors based on chiral organic materials or inorganic structures hold great potential for highly integrated on-chip applications; however, these devices usually have to seek an optimal balance among the asymmetry factor (g), responsivity (R), and stability. Here, we aim to break such a limitation by combining chiral inorganic plasmonic metamaterials with electrical gain, by which one can enhance bothg andR with simultaneously securing the stability. We demonstrate a CPL detector based on “S”-shaped chiral Ag nanowires/InAs/Si heterostructures, where the meticulous construction of the “S”-shaped chiral Ag nanowires with the overlaying InAs channel enables a substantial absorption asymmetry in InAs due to differentiated localized surface plasmon resonances excited by left- and right-circularly polarized (LCP and RCP) light. The InAs serves as a conductive channel, achieving significant electrical gain through photoconductive effects assisted by photogating, gate modulation, and trap effects. The proposed inorganic stable device exhibits a high electricalg of ~ 1.56, an ultra-highR of ~ 33900 A W⁻¹, a large specific detectivity of ~ 1.8×10¹¹Jones, and an ultra-short response time of ~ 23 ns, with the high performance achieved in a broad spectral range from 2 to 2.8 μm. Ultimately, by encoding ASCII code 1 and 0 onto LCP and RCP light, respectively, and leveraging the device's heightened discrimination and response performance to these polarizations, we demonstrate a simple yet key-free optical encryption communication scheme at the device level, highlighting its extensive potential for system-level applications.

摘要：基于手性有机材料或无机结构的圆偏振光（CPL）探测器在高度集成的片上应用中具有巨大潜力，然而，这些器件通常需要在不对称因子(g)、响应度(R)和稳定性之间寻求最佳平衡。本文旨在通过将手性无机等离子体超材料与电增益相结合来突破这一限制，从而在确保稳定性的同时提升g和R值。我们展示了一种基于“S”形手性银纳米线/InAs/Si异质结构的CPL探测器，其中精心构建的“S”形手性银纳米线与覆盖在其周围的InAs通道相结合，由于左旋和右旋圆偏振光（LCP和RCP）激发的局域表面等离子体共振差异，使得InAs中产生了显著的吸收不对称性。InAs作为导电通道，通过光控门、栅极调制和陷阱效应辅助的光电导效应实现了显著的电增益。所提出的无机稳定器件展现出高电学g值~1.56、超高响应度~33900 A W⁻¹、高比探测率~1.8×10¹¹ Jones以及超短响应时间~23 ns的优异性能，且在2 μm至2.8 μm的宽光谱范围内均保持高性能。最终，通过将ASCII码1和0分别编码到LCP和RCP光上，并利用该器件对圆偏振光的高分辨能力和响应性能，我们展示了一个简单且无需秘钥的器件级光加密通信方案，突显了其在系统级应用中的广泛潜力。

影响因子：23.4

链接：https://doi.org/10.1038/s41377-025-01932-9