Application of Electron-Shelving Detection via 423 nm Transition in Calcium-Beam Optical Frequency Standard

A new scheme of small compact optical frequency standard based on thermal calcium beam with application of 423 nm shelving detection and sharp-angle velocity selection detection is proposed. Combining these presented techniques, we conclude that a small compact optical frequency standard based on thermal calcium beam will outperform the commercial caesium-beam microwave dock, like the 5071 Cs clock （from Hp to Agilent, now Symmetricom company）, both in accuracy and stability.     

Microlaser with Ramsey Separated Fields Cavity

In a novel microlaser configuration with Ramsey separated-field cavity, we investigate a two-level atomic beam interacting with a single-mode high-Q Ramsey cavity, which is composed by two separated resonators. By using the well-known Ramsey cavity, one can recover the characters of microlaser even with a high flux atomic beam.     

Variational Approach for the Bose--Hubbard Model

The phase diagram of the one-dimensional Bose-Hubbard model describing interacting bosons in optical lattice is investigated with the variational approach. This method can also be generalized to the two-dimensional case.     

总磷测定仪校准方法

建立总磷测定仪的校准方法。介绍了总磷测定仪的工作原理。总磷测定仪的校准包括温度示值误差和温场均匀性、消解时间示值误差、仪器示值误差、测量重复性、示值稳定性5个项目。利用实验数据确定了总磷测定仪的技术指标:温度示值误差不超过±2℃,温场均匀性不大于3℃,消解时间示值误差为不超过±2%,仪器示值误差为不超过±10%,仪器重复性为不大于5%,示值稳定性为不超过±8%FS。该方法可用于总磷测定仪的校准,保证测量数据的准确可靠。     

气相色谱法检测M15甲醇汽油燃料尾气排放中甲醛的含量

建立了毛细管柱气相色谱法检测甲醛的方法。在GB/T 18204.26–2000方法基础上对色谱条件如色谱柱、柱温等进行优化。在确定的试验条件下吸附剂上甲醛量在0~20μg范围内与色谱峰面积呈现良好的线性,线性相关系数r2=0.999 7,检出限为0.18μg,重复性测定结果的相对标准偏差为1.6%~3.0%(n=8),回收率为103%~110%。利用该方法对M15甲醇汽油汽车尾气样品进行了检测。该法分离效果好、灵敏度高、检测结果准确。     

Kinetic theory of （2＋4）-level atom in σ^＋ -σ^- laser fields

The kinetic theory of (2+4)-level atoms in σ + σ- laser fields is presented.We systemically discuss friction coefficient,momentum diffusion tensor and atomic temperature based on the Fokker-Planck equation.This cooling system is much like that of a (1+3)-level atom,and the temperature is still limited to the Doppler temperature.Since this cooling system has not been investigated before,this work may be regarded as a necessary complement to the laser cooling theory.     

基于分光计使用的系列拓展实验研究

基于传统的分光计实验,结合学校进行的模块化教学改革,进行了相关系列实验的研究,并应用于物理实验教学中,收到了较好的教学效果。