Optical spectra and intensities of graphene magnetic dot bound to a negatively charged Coulomb impurity

doi:https://doi.org/10.1063/1.4891886

Title: Optical spectra and intensities of graphene magnetic dot bound to a negatively charged Coulomb impurity

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Abstract

Employing numerical diagonalization, we study the optical properties of an electron in a monolayer-graphene magnetic dot bound to an off-center negatively charged Coulomb impurity based on the massless Dirac-Weyl model. Numerical results show that, since the electron-hole symmetry is broken by the Coulomb potential, the optical absorption spectra of the magnetic dot in the presence of a Coulomb impurity are different between the electron states and the hole states. Effects of both the magnetic field and the dot size on the absorption coefficient are presented as functions of the incident photon energies.

Authors:

Lee, C. M., E-mail: mesimon-hk@yahoo.com.hk, E-mail: apkschan@cityu.edu.hk; Chan, K. S., E-mail: mesimon-hk@yahoo.com.hk, E-mail: apkschan@cityu.edu.hk ^[1]; Shenzhen Research Institute, City University of Hong Kong, Shenzhen ^[2]

Department of Physics and Materials Science and Center for Functional Photonics, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China)
(China)

Publication Date:: 2014-07-28

OSTI Identifier:: 22308536

Resource Type:: Journal Article

Journal Name:: Journal of Applied Physics

Additional Journal Information:: Journal Volume: 116; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-8979

Country of Publication:: United States

Language:: English

Subject:: 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION; ABSORPTION SPECTRA; COULOMB FIELD; ELECTRONS; GRAPHENE; IMPURITIES; MAGNETIC FIELDS; OPTICAL PROPERTIES; PHOTONS; SIMULATION; SYMMETRY BREAKING

Citation Formats


                    Lee, C. M., E-mail: mesimon-hk@yahoo.com.hk, E-mail: apkschan@cityu.edu.hk, Chan, K. S., E-mail: mesimon-hk@yahoo.com.hk, E-mail: apkschan@cityu.edu.hk, and Shenzhen Research Institute, City University of Hong Kong, Shenzhen. Optical spectra and intensities of graphene magnetic dot bound to a negatively charged Coulomb impurity.  United States: N. p., 2014. 
        Web.  doi:10.1063/1.4891886.

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                    Lee, C. M., E-mail: mesimon-hk@yahoo.com.hk, E-mail: apkschan@cityu.edu.hk, Chan, K. S., E-mail: mesimon-hk@yahoo.com.hk, E-mail: apkschan@cityu.edu.hk, & Shenzhen Research Institute, City University of Hong Kong, Shenzhen. Optical spectra and intensities of graphene magnetic dot bound to a negatively charged Coulomb impurity.  United States.  https://doi.org/10.1063/1.4891886

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                    Lee, C. M., E-mail: mesimon-hk@yahoo.com.hk, E-mail: apkschan@cityu.edu.hk, Chan, K. S., E-mail: mesimon-hk@yahoo.com.hk, E-mail: apkschan@cityu.edu.hk, and Shenzhen Research Institute, City University of Hong Kong, Shenzhen. Mon .  
        "Optical spectra and intensities of graphene magnetic dot bound to a negatively charged Coulomb impurity".  United States.  https://doi.org/10.1063/1.4891886.

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@article{osti_22308536,

  title        = {Optical spectra and intensities of graphene magnetic dot bound to a negatively charged Coulomb impurity},

  author       = {Lee, C. M., E-mail: mesimon-hk@yahoo.com.hk, E-mail: apkschan@cityu.edu.hk and Chan, K. S., E-mail: mesimon-hk@yahoo.com.hk, E-mail: apkschan@cityu.edu.hk and Shenzhen Research Institute, City University of Hong Kong, Shenzhen},

  abstractNote = {Employing numerical diagonalization, we study the optical properties of an electron in a monolayer-graphene magnetic dot bound to an off-center negatively charged Coulomb impurity based on the massless Dirac-Weyl model. Numerical results show that, since the electron-hole symmetry is broken by the Coulomb potential, the optical absorption spectra of the magnetic dot in the presence of a Coulomb impurity are different between the electron states and the hole states. Effects of both the magnetic field and the dot size on the absorption coefficient are presented as functions of the incident photon energies.},

  doi          = {10.1063/1.4891886},

  url          = {https://www.osti.gov/biblio/22308536},
  journal      = {Journal of Applied Physics},

  issn         = {0021-8979},

  number       = 4,

  volume       = 116,

  place        = {United States},

  year         = {2014},

  month        = {7}

}

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