Abstract We have investigated the dispersive properties of excited-doublet four-level atoms interacting with a weak probe field and an intense coupling laser field. We have derived an analytical expression of the dispersion relation for a general excited-doublet four-level atomic system subject to a one-photon detuning. The numerical results demonstrate that for a typical rubidium $\rm {D1}$ line configuration, due to the unequal dipole moments for the transitions of each ground state to double excited states, generally there exists no exact dark state in the system. Close to the two-photon resonance, the probe light can be absorbed or gained and propagate in the so-called superluminal form. This system may be used as an optical switch.
Received: 07 November 2007
Revised: 24 March 2008
Accepted manuscript online:
Fund: Project supported by the Knowledge
Innovation Program (KIP) of the Chinese Academy of Sciences (Grant
No KGCX3-SYW-405) and the National Fundamental Research Program of
China (Grant Nos 2005CB724507 and 2006CB921202).
Cite this article:
Hu Zheng-Feng(胡正峰), Deng Jian-Liao(邓见辽), and Wang Yu-Zhu(王育竹) The dispersive properties of an excited-doubletfour-level atomic system 2008 Chin. Phys. B 17 3358
Observation of spin glass transition in spinel LiCoMnO4 Chen Hong (陈红), Yang Xu (杨旭), Zhang Pei-Song (张培松), Liang Lei (梁磊), Hong Yuan-Ze (洪源泽), Wei Ying-Jin (魏英进), Chen Gang (陈岗), Du Fei (杜菲), Wang Chun-Zhong (王春忠). Chin. Phys. B, 2015, 24(12): 127501.
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