杨贤聪,王迎新,孙国峻,刘键一,周旭,孙文博,华剑飞

• 1:清华大学工程物理系
• 2:清华大学物理系

摘要(Abstract)：

太赫兹时域光谱技术作为电磁波谱中“太赫兹间隙”的重要研究手段,近年来在材料科学、生物医学及无损检测等领域展现出广阔的应用前景,同时也作为前沿科学方向被逐渐引入物理实验教学环节。然而,依托商用太赫兹时域光谱仪的教学平台赋予学生的操作自由度有限,实验流程趋于固定,学生往往仅按步骤执行,对部分关键原理理解不够深入。本文基于自主研发的太赫兹时域光谱仪系统,构建了一套开放式教学实验平台,融合基于光电导天线的太赫兹产生与电光探测技术,重点展现了用于弱信号测量的锁相放大基本原理与技术实现,引导学生在实用化场景中理解信号提取与噪声抑制的技术特征。学生基于自主设定的采样参数,编写代码对原始数据进行傅里叶变换处理,完成从时域波形到吸收光谱的完整分析,从而深入理解太赫兹时域光谱仪基本原理和锁相放大过程。以乳糖一水合物为样品,该平台成功检测了其特征吸收峰,验证了太赫兹时域光谱分析和应用功能的可行性。该实验平台的建设模式与教学实践,对同类太赫兹实验教学平台的构建和应用探索具有较好的参考价值。

关键词(KeyWords)： 太赫兹时域光谱仪;锁相放大;光谱检测;实验教学

Abstract:

Keywords:

基金项目(Foundation): 2024年清华大学本科教育教学改革项目（ZY01-01）;; 清华大学实验室创新基金（202503201）

作者(Author): 杨贤聪,王迎新,孙国峻,刘键一,周旭,孙文博,华剑飞

DOI: 10.27024/j.wlygc.2026.02.13.02

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