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arXiv · 2605.00077

Left handness in a four-level atomic system

Shuncai Zhao·Zhengdong Liu
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Abstract

A scheme is proposed for realizing simultaneous negative permittivity and negative permeability based on quantum coherence in a four-level dense atomic system here.Under some parametric conditions the system shows that simultaneous negative permittivity and negative permeability(i.e.Left handness) can be achieved in a wider frequency band because of quantum coherence.And the novelty properties of gain and dispersion near the resonance frequency may have some potential applications.

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Shuncai Zhao, Zhengdong Liu. 2026-04-30. Left handness in a four-level atomic system. https://doi.org/10.1142/s0219749909005390

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