Soliton Propagation in a Left-handed Four-Level Atomic System

Xiao Yong Yang, Yongyuan Jiang

Xiaoyu Yang, Yongyuan Jiang

Dual bands of left-handedness are obtained in a quasi- four-level atomic system. In our system, multichannel quantum interference plays a very important role on the realization of dual bands. It is shown that the permeability can realize negative values in dual bands of this four-level atomic system. Moreover, the permittivity and permeability can simultaneously realize negative values in the same frequency band. It can be found that the atomic system exhibits negative refraction with low absorption in each left-handed frequency band. At some certain frequencies, this left-handed atomic system can obtain zero absorption.

Dingan Han, Y. Zeng, Yanfeng Bai +5 more

Zhen-Qing Zhang, Zhengdong Liu, Shun‐Cai Zhao +3 more

A closed four-level system in atomic vapour is proposed, which is made to possess left handedness by using the technique of quantum coherence. The density matrix method is utilized in view of the rotating-wave approximation and the effect of a local field in dense gas. The numerical simulation result shows that the negative permittivity and the negative permeability of the medium can be achieved simultaneously (i.e. the left handedness) in a wider frequency band under appropriate parameter conditions. Furthermore, when analysing the dispersion property of the left-handed material, we can find that the probe beam propagation can be controlled from superluminal to subluminal, or vice versa via changing the detuning of the probe field.

Nadia Boutabba, Hichem Eleuch, Habib Bouchriha

Shun-Cai Zhao, Zheng-Dong Liu, Gen Li +1 more

We suggest a scheme for obtaining negative refraction with low absorption in a left-handed atomic system.Under the the appropriate conditions,the atomic system displays negative refraction with negative permittivity and permeability(Left-handedness)in a common frequency range,simultaneously.And the imaginary parts of permittivity and permeability show transparently propagate in the same frequency range.Finally,the negative refraction show low absorption due to the EIT effect,and the figure of merit demonstrated this in this resonant atomic system.