科研之友
微信
新浪微博
Facebook
分享链接
摘要
The Raman-coupled interaction between an atom and a single mode of a cavity field is studied. For the cases in which a light field is initially in a coherent state and in a thermal state separately, we have derived the analytic expressions for the time evolutions of atomic population difference W, modulus B of the Bloch vector, and entropy E. We find that the time evolutions of these quantities are periodic with a period of pi. The maxima of W and B appear at the scaled interaction time points tau = k pi(k = 0, 1, 2....). At these time points, E = 0, which shows that the atom and the field are not entangled. Between these time points, E 74 0, which means that the atom and the field are entangled. When the field is initially in a coherent state, near the maxima, the envelope of W is a Gaussian function with a variance of 1/(4 (n) over bar) ((n) over bar is the mean number of photons). Under the envelope, W oscillates at a frequency of (n) over bar/pi. When the field is initially in a thermal state, near the maxima, W is a Lorentz function with a width of 1/(n) over bar.
- 出版日期2008-4
- 单位华南师范大学
