非共振Jaynes-Cummings模型中强相干光的长时间挤压行为

LONG-TIME BEHAVIOR OF SQUEEZING OF COHERENT LIGHT IN OFF-RESONANCE JAYNES-CUMMINGS MODEL

利用Jaynes-Cummings(缩写为J-C)模型研究了失谐情况下强相干光的长时间挤压行为,其中原子与光场的作用包括单光子跃迁和双光子跃迁两种情况。给出大N极限下挤压度的解析表达式。研究结果表明:对单光子跃迁,失谐(非共振)时的挤压行为定性上与共振时相似,小的失谐对挤压只有小的影响,双光子跃迁时情况不同,失谐起着重要作用。共振时不出现挤压,失谐时才出现挤压,被压缩的不确定度准周期地出现极小,在大N极限下,此极小值系列并趋于零。

The long-time behavior of squeezing of intense coherent light is studied with off-resonance Jaynes-Cummings model. The interaction between field and atom includes both one-photon transition type and two-photon transition type. The analytical formulae for quadrature variances are obtained. In one-photon transition case, small detuning only has small effect on squeezing. For two-photon transition, however, the situation is quite different. No squeezing will occur in resonance case. Only detuning can cause squeezing. Then a series of minimum appear in the suppressed quadrature variance during time evolution. In Urge N limit this se-ries tends to zero.