光钟的发展和应用

 原子频标（原子频率标准的简称）是利用量子力学原理制成的高稳定度和高准确度的频率、时间信号产生系统（成为一个装置时又称为原子钟）。通俗地说，原子钟就像一个计时器一样，记录着时间的流逝。而今天所说的光钟，作为原子钟的一员，顾名思义，就是利用光学频率作参考的原子钟。     

原子的玻色-爱因斯坦凝聚

综述了玻色－－爱因斯坦凝聚（ＢＥＣ）实验研究工作的进展，介绍了玻色－爱因斯坦凝集的概念、形成条件和相关的实验技术，叙述了玻色－爱因斯坦凝集体（ＢＥＣ）和物理性质，展望了发展前景。     

Cluster-state preparation in thermal cavities without single-qubit operation

A potential scheme is proposed for generating cluster states of many atoms in cavity quantum electradynamics （QED）, in which an unorthodox encoding is employed with the ground state being qubit [0〉 while two closely spaced upper states being qubit ｜1〉. Throughout the scheme the cavities can be in thermal states but axe only virtually excited. We show how to create the cluster states by performing a two-step hut no single-qubit operation. Discussion is also carried out on the experimental feasibility of our scheme.     

Paul阱中囚禁的低能Ar2+离子与Ar的电荷转移

在Paul阱中产生并选择囚禁了单一的Ar2 离子,得到低能Ar2 与Ar的电荷转移速率系数为5.84(0.677)×10-10cm3·s-1及其零氩气压强下的离子衰减速率为0.46 s-1,为下一步进行多电荷离子的亚稳态寿命研究提供了有价值的实验参考数据.     

Detection of Isotopes of Mercury Ions by Resonant Ejection in Paul Trap

A simple method to detect mercury ions confined in a Paul trap has been developed by resonant ejection. In this method, frequency of the additional ejection ac voltage is scanned instead of the amplitude of the rf drive voltage in conventional methods. It is possible not only to observe the spectra of the secular oscillation of the trapped ions directly, but also to eject the confined ions from the trap mass-selectively.     

Fluorescence Detection and Buffer Gas Cooling of Trapped Mercury Ions in Paul Trap

Pig ions are confined in a hyperboloid ion trap. With the rf discharge ^202 Hg isotope lamp, the fluorescence signal of trapped Hg ions is observed. By means of buffer gas cooling, the ionic temperature is reduced. As a result, the trapping time is increased and the signal-to-noise ratio （SNR） of the fluorescent signal is improved. The temperature of ion cloud is estimated by measuring the space charge shift.