Enhanced Kerr nonlinearity in a left-handed three-level atomic system driven by a bichromatic field

In a three-level atomic system, the influences of spontaneously generated coherence on the linear absorption and the Kerr nonlinearity are investigated. Our studies show that properties of linear absorption can be dramatically affected by the effect of spontaneously generated coherence. With increase of intensities of spontaneously generated coherence, absorption inhibition will occur, and finally the atomic medium becomes transparent. Furthermore, we find that the Kerr nonlinearity can be obviously enhanced under the action of effects of spontaneously generated coherence. Comparing with traditional scheme of the electromagnetically induced transparency, absorption and Kerr nonlinearity can be controlled without need another driving field in our scheme.

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Toggle switch from optical bistability to multistability via an elliptically polarized field

Modern Physics Letters B ◽

10.1142/s0217984917501913 ◽

2017 ◽

Vol 31 (17) ◽

pp. 1750191 ◽

Cited By ~ 1

Author(s):

Xiang-An Yan ◽

Bo-Quan Ren ◽

Li-Qiang Wang ◽

Yao-Wu Liu ◽

Hua-Wa Yu

Keyword(s):

Quantum Interference ◽

Optical Bistability ◽

Atomic System ◽

Hysteresis Cycle ◽

Toggle Switch ◽

Left Handed ◽

Cycle Shape ◽

Optimal Intensity ◽

The Right ◽

Elliptically Polarized

In this paper, we propose a scheme for manipulating the behavior of optical bistability (OB) and optical multistability (OM) in an N-type four-level atomic system. In the scheme, quantum interference is optimized by the left-handed and the right-handed fields of an elliptically polarized field (EPF). The threshold and the hysteresis cycle shape of OB and OM can be controlled by modulating the intensity of the EPF. Especially, the transition from OB to OM or vice versa can also be easily realized by proper tuning the phase difference between the left-handed and right-handed polarized fields under the optimal intensity of the EPF.

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Left-Handed Material in Five-Level System Based on the Effect of Spontaneously Generated Coherence

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.816-817.242 ◽

2013 ◽

Vol 816-817 ◽

pp. 242-245

Author(s):

Xiang An Yan ◽

Li Qiang Wang

Keyword(s):

Refractive Index ◽

Density Matrix ◽

Quantum Coherence ◽

Atomic System ◽

Negative Refractive Index ◽

Matrix Approach ◽

Level System ◽

Spontaneously Generated Coherence ◽

Left Handedness ◽

Left Handed

We propose a scheme for realizing negative refractive index in a multilevel atomic system. The theoretical modeling has been done using density matrix approach in which the spontaneously generated coherence (SGC) is also induced. It is shown that the negative refractive index can be obtained on the effect of quantum coherence. The parameters () quantifying left-handedness in the system become more negative if the SGC is defined in the appropriate value. Furthermore, left-handed material with reduced absorption is possible by choosing appropriate parameters.

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The Kerr Nonlinearity in an N-Type Four-Level System via Spontaneously Generated Coherence

Journal of Atomic Molecular and Optical Physics ◽

10.1155/2009/382764 ◽

2009 ◽

Vol 2009 ◽

pp. 1-4 ◽

Cited By ~ 3

Author(s):

Yingjie Du ◽

Kang Jin ◽

Junxiang Zhang

Keyword(s):

Atomic System ◽

Kerr Nonlinearity ◽

Level System ◽

Probe Field ◽

Spontaneously Generated Coherence

The Kerr nonlinearity is investigated in an N-type four-level atomic system whose both supper levels are degenerated or nearly degenerate. It is found that the spontaneously generated coherence as a result of the degenerate levels can change the Kerr nonlinearity dramatically depending on the angle between two spontaneous channels. In addition, we discover that the probe field makes its own contribution to the nonlinearity in comparison to indifference in general three-level systems.

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