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Title: Quantum beats in conductance oscillations in graphene-based asymmetric double velocity wells and electrostatic wells

Abstract

The transport properties in graphene-based asymmetric double velocity well (Fermi velocity inside the well less than that outside the well) and electrostatic well structures are investigated using the transfer matrix method. The results show that quantum beats occur in the oscillations of the conductance for asymmetric double velocity wells. The beating effect can also be found in asymmetric double electrostatic wells, but only if the widths of the two wells are different. The beat frequency for the asymmetric double well is exactly equal to the frequency difference between the oscillation rates in two isolated single wells with the same structures as the individual wells in the double well structure. A qualitative interpretation is proposed based on the fact that the resonant levels depend upon the sizes of the quantum wells. The beating behavior can provide a new way to identify the symmetry of double well structures.

Authors:
 [1];  [2]; ;  [1];  [1];  [2]
  1. Hebei Advanced Thin Films Laboratory, College of Physical Science and Information Engineering, Hebei Normal University, Shijiazhuang, Hebei 050024 (China)
  2. (China)
Publication Date:
OSTI Identifier:
22271265
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 2; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 77 NANOSCIENCE AND NANOTECHNOLOGY; ASYMMETRY; ELECTRIC CONDUCTIVITY; ENERGY LEVELS; GRAPHENE; OSCILLATIONS; QUANTUM WELLS; SYMMETRY; TRANSFER MATRIX METHOD; VELOCITY

Citation Formats

Liu, Lei, Department of Medical Physics, Basic Medical College, Hebei Medical University, Shijiazhuang, Hebei 050017, Li, Yu-Xian, Zhang, Ying-Tao, Liu, Jian-Jun, E-mail: liujj@mail.hebtu.edu.cn, and Physics Department, Shijiazhuang University, Shijiazhuang, Hebei 050035. Quantum beats in conductance oscillations in graphene-based asymmetric double velocity wells and electrostatic wells. United States: N. p., 2014. Web. doi:10.1063/1.4861381.
Liu, Lei, Department of Medical Physics, Basic Medical College, Hebei Medical University, Shijiazhuang, Hebei 050017, Li, Yu-Xian, Zhang, Ying-Tao, Liu, Jian-Jun, E-mail: liujj@mail.hebtu.edu.cn, & Physics Department, Shijiazhuang University, Shijiazhuang, Hebei 050035. Quantum beats in conductance oscillations in graphene-based asymmetric double velocity wells and electrostatic wells. United States. doi:10.1063/1.4861381.
Liu, Lei, Department of Medical Physics, Basic Medical College, Hebei Medical University, Shijiazhuang, Hebei 050017, Li, Yu-Xian, Zhang, Ying-Tao, Liu, Jian-Jun, E-mail: liujj@mail.hebtu.edu.cn, and Physics Department, Shijiazhuang University, Shijiazhuang, Hebei 050035. Tue . "Quantum beats in conductance oscillations in graphene-based asymmetric double velocity wells and electrostatic wells". United States. doi:10.1063/1.4861381.
@article{osti_22271265,
title = {Quantum beats in conductance oscillations in graphene-based asymmetric double velocity wells and electrostatic wells},
author = {Liu, Lei and Department of Medical Physics, Basic Medical College, Hebei Medical University, Shijiazhuang, Hebei 050017 and Li, Yu-Xian and Zhang, Ying-Tao and Liu, Jian-Jun, E-mail: liujj@mail.hebtu.edu.cn and Physics Department, Shijiazhuang University, Shijiazhuang, Hebei 050035},
abstractNote = {The transport properties in graphene-based asymmetric double velocity well (Fermi velocity inside the well less than that outside the well) and electrostatic well structures are investigated using the transfer matrix method. The results show that quantum beats occur in the oscillations of the conductance for asymmetric double velocity wells. The beating effect can also be found in asymmetric double electrostatic wells, but only if the widths of the two wells are different. The beat frequency for the asymmetric double well is exactly equal to the frequency difference between the oscillation rates in two isolated single wells with the same structures as the individual wells in the double well structure. A qualitative interpretation is proposed based on the fact that the resonant levels depend upon the sizes of the quantum wells. The beating behavior can provide a new way to identify the symmetry of double well structures.},
doi = {10.1063/1.4861381},
journal = {Journal of Applied Physics},
number = 2,
volume = 115,
place = {United States},
year = {Tue Jan 14 00:00:00 EST 2014},
month = {Tue Jan 14 00:00:00 EST 2014}
}
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