Chin. Phys. B ›› 2013, Vol. 22 ›› Issue (4): 47203-047203.doi: 10.1088/1674-1056/22/4/047203

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Design of electron wave filters in monolayer graphene with velocity modulations

孙立风a, 董利民b, 房超a   

  1. a Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China;
    b Beijing Key Laboratory of Fine Ceramics, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
  • 收稿日期:2012-09-24 修回日期:2012-11-30 出版日期:2013-03-01 发布日期:2013-03-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 11104156), the Postdoctoral Science Foundation of China (CPSF) (Grant No. 2012M510405), the Independent Research and Development Fund of Tsinghua University (Grant No. 20121087948), and Beijing Key Laboratory of Fine Ceramics Opening Fund (Grant No. 2012200110).

Design of electron wave filters in monolayer graphene with velocity modulations

Sun Li-Feng (孙立风)a, Dong Li-Min (董利民)b, Fang Chao (房超)a   

  1. a Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China;
    b Beijing Key Laboratory of Fine Ceramics, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
  • Received:2012-09-24 Revised:2012-11-30 Online:2013-03-01 Published:2013-03-01
  • Contact: Fang Chao E-mail:fangchao@mail.tsinghua.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 11104156), the Postdoctoral Science Foundation of China (CPSF) (Grant No. 2012M510405), the Independent Research and Development Fund of Tsinghua University (Grant No. 20121087948), and Beijing Key Laboratory of Fine Ceramics Opening Fund (Grant No. 2012200110).

摘要: We compare the transport properties of electrons in monolayer graphene by modulating the Fermi velocity inside the barrier. A critical transmission angle is found only when the Fermi velocity in the barriers is larger than the one outside the barriers. It is shown that the transmission exhibits periodicity with the incident angle below the critical transmission angle, and attenuates exponentially in the opposite situation. For both situations, peak splitting occurs in the transmission as the number of the velocity barriers increases, and the characteristics of the transmission suggest an interesting application of an excellent band-pass filter. The dependence of the conductance on the Fermi energy through identical velocity-modulation structure differs wildly with different Fermi velocities of the barrier. The counterpart of the peak splitting is the sharp oscillations in the conductance profile. Furthermore, some oscillations for the multiple barriers are so sharp that the structure may be used as an excellent sensor.

关键词: velocity modulation, periodicity, peak splitting, sharp oscillations

Abstract: We compare the transport properties of electrons in monolayer graphene by modulating the Fermi velocity inside the barrier. A critical transmission angle is found only when the Fermi velocity in the barriers is larger than the one outside the barriers. It is shown that the transmission exhibits periodicity with the incident angle below the critical transmission angle, and attenuates exponentially in the opposite situation. For both situations, peak splitting occurs in the transmission as the number of the velocity barriers increases, and the characteristics of the transmission suggest an interesting application of an excellent band-pass filter. The dependence of the conductance on the Fermi energy through identical velocity-modulation structure differs wildly with different Fermi velocities of the barrier. The counterpart of the peak splitting is the sharp oscillations in the conductance profile. Furthermore, some oscillations for the multiple barriers are so sharp that the structure may be used as an excellent sensor.

Key words: velocity modulation, periodicity, peak splitting, sharp oscillations

中图分类号:  (Electronic transport in graphene)

  • 72.80.Vp
73.23.Ad (Ballistic transport) 73.40.Gk (Tunneling)