High‐sensitivity impulsive stimulated Raman spectrometer with fast data acquisition,Journal of Raman Spectroscopy

当前位置： X-MOL 学术 › J. Raman Spectrosc. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

High‐sensitivity impulsive stimulated Raman spectrometer with fast data acquisition
Journal of Raman Spectroscopy ( IF 2.4 ) Pub Date : 2020-11-22 , DOI: 10.1002/jrs.6048
Mauro Falconieri ₁ , Serena Gagliardi ₁ , Flaminia Rondino ₁ , Michele Marrocco ₁ , Waruna D. Kulatilaka ₂

Affiliation

Impulsive stimulated Raman scattering (ISRS) is a nonlinear coherent technique for the measurement of the vibrational spectrum of samples within the bandwidth of the excitation laser pulse, which, for pulse durations of several tens of femtoseconds, translates into easy access to the low‐wavenumber Raman spectrum (below few hundreds of cm⁻¹). Recently, a degenerate ISRS Fourier‐transform Michelson spectrometer for measurements in bulk, transparent liquids operating with a single, nonamplified femtosecond laser source, was demonstrated, although with low measurement speed, exploiting a position‐sensitive detector to measure the time evolution of the tiny spectral asymmetries of the probe beam produced by stimulated Raman gain and loss. Building on this innovation of the detection method, in this work, we show that using a different data acquisition concept, based on the fast modulation of the delay in one of the spectrometer arms, it is possible to measure scattering and absorbing samples in a much shorter time, approaching the real‐time visualization of the Raman spectrum of the sample under analysis. Furthermore, the setup described here does not suffer from creation of microbubbles, heating effects or thermal instabilities produced in the sample by increasingly high excitation fluences, and is therefore suitable to be implemented in vibrational microscopy applications with tight beam focusing. Thus, the present work is a contribution toward practical implementation of low‐wavenumber vibrational imaging, which is of importance for studies of intramolecular vibrational modes of large molecules or of heavy functional groups or for the study of intermolecular force constants in biological and nanostructured materials.

中文翻译：

高灵敏度脉冲激发拉曼光谱仪，可快速采集数据

脉冲受激拉曼散射（ISRS）是一种非线性相干技术，用于测量激发激光脉冲带宽内的样品振动谱，对于几十飞秒的脉冲持续时间，这意味着可以轻松访问低波数。拉曼光谱（低于几百厘米^-1）。最近，展示了一种简并的ISRS傅里叶变换迈克尔逊光谱仪，该光谱仪使用单个非放大的飞秒激光源进行批量透明液体的测量，尽管测量速度较低，但它利用位置敏感检测器来测量微小的时间演化。由受激拉曼增益和损耗产生的探测光束的光谱不对称性。在这项检测方法的创新基础上，在这项工作中，我们表明，使用不同的数据采集概念，基于光谱仪臂之一中延迟的快速调制，可以测量大量样品中的散射和吸收更短的时间，接近分析样品的拉曼光谱的实时可视化。此外，此处所述的设置不会因越来越高的激发通量而产生样品中的微气泡，加热效应或热不稳定性，因此适合在具有紧密束聚焦的振动显微镜应用中实施。因此，本工作为低波数振动成像的实际实施做出了贡献，这对于研究大分子或重官能团的分子内振动模式或研究生物和纳米结构材料中的分子间力常数非常重要。

更新日期：2020-11-22

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11