权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Studies on New Spectrometric Light Source -Rainbow Stars-

新型光谱光源的研究-彩虹星-

基本信息

批准号：
01850171
负责人：
IMASAKA Totaro
金额：
$ 10.5万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1991
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-01850171/
关键词：
Rainbow Stars Widely-Tunable Laser Multi-Color Laser Four-Wave Mixing Stimulated Raman Effect Spectroscopic Analysis Fydrogen Ultrashort Laser Pulse 色素レ-ザ-光源

项目摘要

Two-color stimulated Raman emission was generated by introduction of a two-color laser beam into pressurized hydrogen, in order to obtain widely-tunable laser emission. The laser wavelength could be changed from 247 to 771 nm. However, it was technically difficult to simultaneously scan both the laser wavelengths. Then, a few numbers of rotational stimulated Raman lines were first generated by introduction of a circularly-polarized, single-color laser beam. Succeedingly, the polarization was changed to a linear, and many rotational and vibrational lines were generated by the two-color stimulated Raman effect. This technique allows a wavelength scan and is useful for analytical spectroscopy. It was also possible to generate either vibrational or rotational lines selectively by optimizing the polarization of the beam. the pressure of hydrogen, and the beam focusing condition. Alternatively. the separation of the rotational lines could be changed from 587 to 354 cm^<-1> by replacing ortho … More -hydrogen with para-hydrogen. This approach is useful to increase the density of the rotational lines in the specified spectral region.Equally-spaced, multi-frequency laser emission can, be generated by two-color stimulated Raman emission. As is known from Uncertainty principle, ultrashort light pulses can be generated by the laser with wide frequency components. Then, the presented approach might give a break-through in generation of ultrashort pulses. Theoretical and preliminary experimental works were performed in this study. By a theoretical calculation, a laser pulse with several fs could be generated, when the laser beam was Fourier-transform limited and was modelocked. Several optical configurations for generation of ultrashort pulses were proposed, e. g. a quenching laser/short-cavity laser/distributed feedback laser/exciter laser amplification/two-color stimulated Raman emission. - In our preliminary study, a 2-ns laser pulse was generated by quenching the long tail of the dye laser pulse. It was verified that a high-power, sh(Yrt-pulse laser is useful for efficient generation of two-color stimulated Raman emission. The multi-pass Raman cell developed in our laboratory was useful for reduction of threshold and improvement of the efficiency.Two-color stimulated Raman emission was used as a light source for excitation of the sample in a condensed phase and in a supersonic jet. Thus it was verified to be useful for measurement of the sample in analytical spectroscopy. Less

将双色激光束引入加压氢气中，产生双色受激拉曼发射，以获得宽可调谐的激光发射。激光波长可在247 ~ 771 nm范围内变化。然而，同时扫描两种激光波长在技术上是困难的。然后，通过引入圆偏振单色激光束，首先产生了少量的旋转受激拉曼线。利用双色受激拉曼效应，成功地将极化转变为线性，并产生了许多旋转线和振动线。这种技术允许波长扫描，对分析光谱学很有用。通过优化光束的偏振，也可以选择性地产生振动线或旋转线。氢气的压力，以及光束聚焦的条件。另外。用对氢取代正位多氢，可使旋转线的间距从587 cm^<-1>增加到354cm ^<-1>。这种方法有助于增加指定光谱区域内旋转谱线的密度。双色受激拉曼发射可以产生等间距、多频率的激光发射。由测不准原理可知，宽频率分量的激光可以产生超短光脉冲。因此，所提出的方法可能会在超短脉冲的产生方面取得突破。本研究进行了理论和初步实验工作。通过理论计算，当激光束受傅里叶变换限制并被模型锁定时，可以产生几个fs的激光脉冲。提出了几种产生超短脉冲的光学结构：淬火激光器/短腔激光器/分布反馈激光器/激发器激光放大/双色受激拉曼发射。在我们的初步研究中，通过对染料激光脉冲的长尾进行淬火，产生了一个2ns的激光脉冲。实验验证了高功率sh（yrt）脉冲激光器可以有效地产生双色受激拉曼辐射。本实验室研制的多通道拉曼细胞有助于降低阈值，提高效率。采用双色受激拉曼发射作为光源，对凝聚态和超音速射流中的样品进行了激发。从而验证了该方法在分析光谱中对样品的测量是有用的。少