Abstract Using a time-dependent multilevel approach, we demonstrate that lithium atoms can be transferred to states of lower principle quantum number by exposing them to a frequency chirped microwave pulse. The population transfer from n = 79 to n = 70 states of lithium atoms with more than 80% efficiency is achieved by means of the sequential two-photon $\varDelta n = - 1$ transitions. It is shown that the coherent control of the population transfer can be accomplished by the optimization of the chirping parameters and microwave field strength. The calculation results agree well with the experimental ones and novel explanations have been given to understand the experimental results.
Received: 03 December 2008
Revised: 03 April 2009
Accepted manuscript online:
Fund: Project supported by the National
Natural Science Foundation of China (Grant No 10774039).
Cite this article:
Jia Guang-Rui(贾光瑞), Zhang Xian-Zhou(张现周), Ren Zhen-Zhong(任振忠), and Wu Su-Ling(伍素玲) Lithium atom population transfer by population trapping in a chirped microwave pulse 2009 Chin. Phys. B 18 5272
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