【作者】 王进； 程存峰； 谈艳； 刘安雯； 胡水明；

【Author】 Jin Wang;Cunfeng Cheng;Yan Tan;Anwen Liu;Shuiming Hu;Hefei National Laboratory for Physical Science at the Microscale,Department of Chemical Physics, University of Science and Technology of China;

【机构】 合肥微尺度物质科学国家实验室中国科学技术大学化学物理系；

【摘要】 氢分子是最基本的分子,也是目前唯一的在理论和和实验上都有望达到极高精度的中性分子。高精密的氢分子光谱,特别是其电子基态的能级结构,可以检验高精度量子化学计算方法甚至基本物理常数。作为同核双原子分子,氢分子不存在电偶极红外振转跃迁,仅有极微弱的电四极矩跃迁。本项目计划利用高灵敏的光腔衰荡光谱技术,结合激光精密稳频技术,实现等效吸收光程达数千千米、光谱测量精度好于10-5cm-1的光腔衰荡光谱探测,对氢分子近红外泛频振转光谱进行高精密测量,对包含相对论和高阶量子电动力学修正的高精度量子化学理论进行直接的检验,并探讨在该分子体系中实现对电子/质子之比等基本物理常数进行测定。更多还原

【Abstract】 Molecular hydrogen is the most fundamental, and the only neutral molecule expected to be both calculated and measured with extremely high accuracy. High-precision measurements of its spectroscopy, especially the levels at the electric ground state, play an important role in the examination of precise quantum chemistry calculations and some fundamental physical constants. In the infrared region, H2, being a homonuclear diatomic molecule, only has very weak electric quadrupole transitions. We established a new spectroscopy approach with ultra-high precision and sensitivity as well, based on a laser-locked cavity ring-down spectrometer. An equivalent absorption path-length of thousands of kilometers and a frequency precision of 10-5 cm-1have been achieved. Ro-vibrational spectra of the second overtone of H2 have been recorded. The obtained results will provide a direct examination of the high-accuracy quantum theory. It also shades light on the determination of fundamental physical constants such as the electron/proton mass ratio in a molecular system.更多还原