http://reply.papertrans.cn/2/188/18757/18757-31.png
http://reply.papertrans.cn/2/188/18757/18757-32.png
http://reply.papertrans.cn/2/188/18757/18757-33.png
Submitted on: 23 May 2006.
Revised on: 28 June 2006.
Accepted on: 17 July 2006.
___________________JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
http://reply.papertrans.cn/2/188/18757/18757-35.png
Submitted on: 04 March 2008.
Revised on: 01 July 2008.
Accepted on: 25 August 2008.
___________________JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS