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arXiv · 2403.00848

Effect of spontaneously generated coherence on left-handedness in a degeneracy atomic system

Shun-Cai Zhao
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Abstract

A theoretical investigation is carried out into the effect of spontaneously generated coherence(SGC) on the left-handedness in a four-level Y-type atomic system with two highest nearly degenerate lying levels. It is found, with the spontaneously generated coherence intensity enhancing, the atomic system gradually displays left-handedness with simultaneous negative permittivity and permeability. And the refractive index enhances with the increasing intensity of SGC.However, the absorption is suppressed by the SGC effect when the SGC has a large intensity.When the probe field is near-resonant coupled to the atomic system, the appearance of SGC doesn't always change the permeability from positive to negative and allow for left-handed behavior,unless the SGC reaches a large intensity.

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Shun-Cai Zhao. 2024-02-29. Effect of spontaneously generated coherence on left-handedness in a degeneracy atomic system. https://doi.org/10.1134/s0021364011170176

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