Left-handedness without absorption in the four-level Y-type atomic medium  

作　　者：赵顺才 刘正东 吴奇宣 

机构地区：[1]School of Materials Science and Engineering,Nanchang University [2]Engineering Research Center for Nanotechnology,Nanchang University [3]Institute of Modern Physics,Nanchang University [4]College English department,Hainan University

出　　处：《Chinese Physics B》2010年第1期350-354,共5页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 60768001 and 10464002)

摘　　要：In this paper we have investigated three external fields interacting with the four-level Y-type atomic system described by the density-matrix approach. The results show that left-handedness with zero absorption is achieved. The zero absorption property displays the possibility of manipulation by varying the phase and the intensity of the coupling field. Also, the zero absorption property may be used to amplify the evanescent waves that have been lost in imaging by traditional lenses. We propose an approach to obtain a negative refractive medium with zero absorption and the possibility of enhaneeingthe imaging resolution in realizing ＇superlenses＇.In this paper we have investigated three external fields interacting with the four-level Y-type atomic system described by the density-matrix approach. The results show that left-handedness with zero absorption is achieved. The zero absorption property displays the possibility of manipulation by varying the phase and the intensity of the coupling field. Also, the zero absorption property may be used to amplify the evanescent waves that have been lost in imaging by traditional lenses. We propose an approach to obtain a negative refractive medium with zero absorption and the possibility of enhaneeingthe imaging resolution in realizing ＇superlenses＇.

关 键 词：zero absorption LEFT-HANDEDNESS negative refractive index negative permittivity and permeability 

分 类 号：O431.2[机械工程—光学工程] O562[理学—光学]