J4 ›› 2013, Vol. 30 ›› Issue (4): 507-512.

• 纤维与波导光学 • 上一篇    

双层石墨烯非对称波导中导模性质的分析

彭娉 李冠强 冯海涛 刘建科   

  1. 陕西科技大学理学院,陕西 西安,710021
  • 收稿日期:2012-07-18 修回日期:2013-04-10 出版日期:2013-07-28 发布日期:2013-07-06
  • 通讯作者: 彭娉(1981-),女,湖南人,讲师,从事低维纳米材料与器件的研究。 E-mail:pengping@sust.edu.cn
  • 基金资助:
    咸阳市科学技术研究发展计划项目(2012k16-09),陕西省教育厅自然科学基金项目(12JK0961) ,陕西省自然科学基础研究计划资助项目(11JK0556)

Analysis on characteristics of guided modes in bilayer graphene-based asymmetric waveguides

PENG Ping, LI Guan-qiang, FENG Hai-tao, LIU Jian-ke   

  1. College of Science, Shaanxi University of Science and Technology,Xi’an,710021,China
  • Received:2012-07-18 Revised:2013-04-10 Published:2013-07-28 Online:2013-07-06

摘要: 研究了基于双层石墨烯的非对称量子阱波导中导模的性质。当石墨烯中电子的入射能一定时,通过控制加在石墨烯不同区域的直流电压,可使狄拉克费米子在非对称波导中存在三种不同类型的运动方式,即准经典运动、量子克莱恩隧穿以及二者的混合运动。在解析推导出导模色散关系的基础上,详细讨论了三种不同情形下导模的结构特征。该研究结果对于石墨烯波导器件的实际应用具有重要意义。

关键词: 光电子学, 非对称导模, 连续性条件, 色散关系, 双层石墨烯

Abstract: Based on the Hamiltonian of carriers in bilayer graphene, the characteristic of the guided modes in asymmetric quantum-well waveguides is investigated. There exist three different kinds of motions depending on the incident energy of the electrons and the external potentials, i. e., quasi-classical motion, quantum Klein tunneling, and mixing of the former two. Given the wave functions for the different regions and using the continuity conditions at the interfaces of the potential barriers, the dispersion relationship for the guided modes in asymmetric waveguides is derived analytically. Meanwhile, the structure feature of the guided modes under three different cases is discussed. The study is very significant for the practical applications of graphene-based waveguide devices.

Key words: optoelectronics, asymmetric guided mode, continuity condition, dispersion relationship, bilayer graphene

中图分类号: