Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1539744 | Optics Communications | 2008 | 5 Pages |
Abstract
We propose a new scheme for realizing left-handed electromagnetic properties in a coherently driven four-level system. At the presence of spontaneously generated coherence and the local field effect, both dielectric permittivity and magnetic permeability may have negative real parts of the same order in a small frequency band. Thus, one can achieve the negative refractive index and then manipulate it by modulating the coherent field or changing the atomic density. With incoherent pumping applied to have more remarkable spontaneously generated coherence, one can further obtain a wider frequency band of negative refraction and simultaneously reduce the accompanied absorption.
Related Topics
Physical Sciences and Engineering
Materials Science
Electronic, Optical and Magnetic Materials
Authors
Nuo Ba, Jin-Wei Gao, Wei Fan, Da-Wei Wang, Qi-Rong Ma, Rong Wang, Jin-Hui Wu,