对高精度激光光谱学和许多物理常数的测量而言 ,发射极确定波长的激光至关重要。比如 ,光学时钟利用原子的光学共振确定时钟频率。如能进一步减小激光的“谱线宽度”,则可望进一步提高精度。美国国家标准技术研究院的 B.Young和同事们建立了一种发射可见光的谱线宽度比以前窄 1 For high-precision laser spectroscopy and the measurement of many physical constants, it is important that the laser emits light of a certain wavelength. For example, the optical clock uses atomic optical resonance to determine the clock frequency. If the laser can further reduce the “spectral width”, it is expected to further improve the accuracy. B. You and colleagues at the National Institute of Standards and Technology have established a spectral line that emits visible light that is narrower than before