PT对称光晶格中的缺陷暗孤子

J4 ›› 2015, Vol. 32 ›› Issue (6): 728-734.

PT对称光晶格中的缺陷暗孤子

易向东，谢庆文，罗质华, 石智伟，朱兴，李华刚

1 广东第二师范学院物理系，广东广州 510303； 2 广东工业大学信息工程学院，广东广州 510006

出版日期:2015-11-28 发布日期:2015-11-05
通讯作者: 李华刚 (1975-)河北人，副教授，硕士，从事激光传输的理论研究。 E-mail:lihuagang@gdei.edu.cn
作者简介:易向东 (1980-)湖南人，讲师，硕士，从事信息技术的理论和应用研究。yixiangdong@gdei.edu.cn
基金资助:
中国博士后科学基金（2013M531822），广东省自然科学基金(S2012040007188)资助

Defect dark solitons in PT-symmetric optical lattices

Yi Xiangdong，Xie Qingwen，Luo Zhihua ， Shi Zhiwei， Zhu Xing ，Li Huagang

1 Department of Physics, Guangdong university of Education, Guangzhou 510303, China； 2 School of Information Engineering, Guangdong University of Technology, Guangzhou 510006, China

Published:2015-11-28 Online:2015-11-05

摘要/Abstract

摘要：

数值研究了实部具有缺陷的parity-time对称光晶格中的缺陷暗孤子。当衍射与自散焦非线性效应平衡时，暗孤子能够被获得；当自散焦介质中的parity-time对称光晶格实部被附加一个缺陷后，缺陷暗孤子也能够被获得。数值结果显示：缺陷暗孤子可以在很大参数范围内存在并且能稳定传播；parity-time对称光晶格实部附加的缺陷强度有一最大值，超过此值缺陷暗孤子不存在；parity-time对称光晶格的虚部振幅对缺陷暗孤子的稳定性有影响。

关键词: 非线性光学, 缺陷暗孤子, Parity-time对称光晶格, 稳定性

Abstract:

Defect dark solitons were numerically researched in parity-time-symmetric optical lattices with an additional defect in the real part. When the diffraction is balanced with the self-defocusing nonlinear effect, dark solitons can be obtained; when a defect is added in the real part of parity-time-symmetric optical lattices, defect dark solitons can also be obtained. Numerical results showed that defect dark solitons can exist and be stable in large parameters range; the strength of additional defect has a maximum value, and the defect dark solitons do not exist above this value; the amplitude of the imaginary part of parity-time-symmetric optical lattices can affect the stability of the defect dark solitons.

Key words: Nonlinear optics, Defect dark solitons, Parity-time-symmetric optical lattice, Stability

易向东，谢庆文，罗质华, 石智伟，朱兴，李华刚. PT对称光晶格中的缺陷暗孤子[J]. J4, 2015, 32(6): 728-734.

Yi Xiangdong，Xie Qingwen，Luo Zhihua ， Shi Zhiwei， Zhu Xing ，Li Huagang. Defect dark solitons in PT-symmetric optical lattices[J]. J4, 2015, 32(6): 728-734.

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