Phase-dependent inversionless gain in a four-level atomic system with a closed interaction loop
Xu Wei-Hua(徐卫华)a)†, Wu Jin-Hui(吴金辉)b)c), and Gao Jin-Yue(高锦岳)b)c)
a College of Physics, Shenzhen University, Shenzhen 518060, Chinab College of Physics, Jilin University, Changchun 130023, China; b Key Laboratory for Coherent Light, Atomic and Molecular Spectroscopy of Ministry of Education, Jilin University, Changchun 130023, China
Abstract A four-level atomic system with a closed interaction loop connected by two coherent driving fields and a microwave field is investigated. The results show that inversionless gain can be achieved on a higher frequency transition outside the closed interaction loop, and the gain behaviour can be modulated by the phase of the closed loop as well as the amplitude of the microwave field. The phase sensitivity property in such a scheme is similar to that in an analogous configuration with spontaneously generated coherence, but it is beyond the rigorous condition of near-degenerate levels with non-orthogonal dipole moments. Therefore this scheme is much more convenient in experimental realization.
Received: 14 March 2006
Revised: 09 August 2006
Accepted manuscript online:
PACS:
42.50.Gy
(Effects of atomic coherence on propagation, absorption, and Amplification of light; electromagnetically induced transparency and Absorption)
(Quantum description of interaction of light and matter; related experiments)
Fund: Project supported by the Natural Science Foundation of Guangdong Province (Grant No 05301018), the Research and Development Fund of Shenzhen University, China (Grant No 200549), and the National Natural Science Foundation of China (Grant Nos 10334010 and 10404009).
Cite this article:
Xu Wei-Hua(徐卫华), Wu Jin-Hui(吴金辉), and Gao Jin-Yue(高锦岳) Phase-dependent inversionless gain in a four-level atomic system with a closed interaction loop 2007 Chinese Physics 16 441
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