Istituto Nazionale di Ottica, INO-CNR, & European Laboratory for Nonlinear Spectroscopy, LENS, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy.
Phys Chem Chem Phys. 2019 Nov 13;21(44):24506-24511. doi: 10.1039/c9cp02941a.
As molecular spectroscopy makes its comeback to the limelight of fundamental sciences, scientists need ever better coherent light sources and diagnostic methods. Of particular importance for molecular spectroscopy is the mid infrared spectral region, where strong and narrow ro-vibrational excitations have their fundamental transition frequencies. Unfortunately, much technology in some portions of this spectral region is still rather pioneering. Here we present a high-resolution spectroscopy experiment, based on a molecular beam setup, which pushes the measured linewidth close to the transit time limit, on the order of 100 kHz. Moreover, we discuss the issue of frequency-noise characterization and the linewidth measurement of the ultrastable infrared laser used in the experiment.
随着分子光谱学重新成为基础科学的焦点，科学家们需要更好的相干光源和诊断方法。对于分子光谱学来说，特别重要的是中红外光谱区域，其中强而窄的 ro-振动激发具有其基本跃迁频率。不幸的是，该光谱区域的某些部分的许多技术仍然具有开创性。在这里，我们提出了一个基于分子束装置的高分辨率光谱实验，该实验将测量的线宽推近于传输时间极限，约为 100 kHz。此外，我们还讨论了实验中使用的超稳定红外激光的频率噪声特性和线宽测量问题。
