近日，清华大学方璐团队报道了集成铌酸锂光子学用于亚纳米快拍光谱。这一研究成果于2025年10月15日发表在《自然》杂志上。

光谱学是解析物质结构与环境化学成分的关键技术，已广泛应用于多个科学领域。传统光谱技术依赖窄缝或光栅结构，必须在光谱分辨率与透射率之间进行权衡，因而无法同时实现高灵敏度与高效率测量。

研究组提出的RAFAEL技术——一种亚埃级超高透射率快照式光谱方法，通过基于铌酸锂的集成可重构光子学架构突破了这一局限。该设计以块状铌酸锂作为具备像素级电控光谱响应的干涉掩模，在保持高光学透射率的同时实现了皮米级光谱调制。该方案在400-1000纳米波段达成0.5埃光谱分辨率（R=12,000）、2048×2048空间分辨率与73.2%总透射率，每秒可完成88次瞬态光谱采集。

经多组实验验证，相较于现有顶尖光谱成像仪，RAFAEL将总透射率提升两倍，光谱分辨能力增强近两个数量级。特别值得关注的是，RAFAEL单次曝光即可捕获5600颗恒星的亚埃级光谱（含全部原子吸收峰），其观测效率较世界顶级天文光谱仪提升100至10000倍。这种高性能且易集成的快照式光谱技术将推动从材料科学到天体物理等领域的突破性进展。

附：英文原文

Title: Integrated lithium niobate photonics for sub-ngstrm snapshot spectroscopy

Author: Yao, Zhiyang, Liu, Shuyang, Wang, Yingce, Yuan, Xiaoyun, Fang, Lu

Issue&Volume: 2025-10-15

Abstract: Spectroscopy is a pivotal tool for determining the physical structures and chemical compositions of materials and environments, and it is commonly used across diverse scientific fields1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16. Conventionally, spectroscopic techniques rely on narrow slits or gratings, which impose a trade-off between spectral resolution and optical transmittance17,18,19,20,21,22, thus precluding measurements with simultaneous high sensitivity and high efficiency. Here we introduce RAFAEL, a sub-ngstrm ultra-high-transmittance snapshot spectroscopic technique, which targets this trade-off with integrated and reconfigurable photonics based on lithium niobate. Its design comprises bulk lithium niobate as an interference mask with a pixel-wise electrically tunable spectral response and delivers picometre-scale modulation with a high optical transmittance. Our approach achieves 88-Hz snapshot spectroscopy with a spectral resolution of approximately 0.5 at 400–1,000nm (R=12,000), spatial resolution of 2,048×2,048 and 73.2% total optical transmittance. Compared with state-of-the-art spectroscopic imagers23,24,25,26,27,28,29,30,31,32,33,34, RAFAEL offers double the total transmittance and a nearly two orders of magnitude improvement in spectral resolving power, as verified by extensive experiments. In particular, RAFAEL captured sub-ngstrm spectra, including all atomic absorption peaks, of up to 5,600 stars in a single snapshot, indicating ×100–10,000 improvement in observational efficiency compared with world-class astronomical spectrometers17,18,19,20,21. This high-performing yet easily integrated snapshot spectroscopic method could drive advances in fields ranging from material science to astrophysics.

DOI: 10.1038/s41586-025-09591-x

Source: https://www.nature.com/articles/s41586-025-09591-x