Trapping electrons in a circular graphene quantum dot with Gaussian potential

Nhung T. T. Nguyen
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Authors

  • Nhung T. T. Nguyen Institute of Physics, Vietnam Academy of Science and Technology

DOI:

https://doi.org/10.15625/0868-3166/28/1/11080

Keywords:

quasi-bound state, localization, trapping time

Abstract

We study the dependence of trapping time of an electron in a circular graphene quantum dot

depends on the electron's angular momentum and on the parameters of the

external Gaussian potential used to induce the dot. The trapping times are

calculated through a numerical determination of the quasi-bound states of

electron from the two-dimensional Dirac-Weyl equation. It is shown that on

increasing the angular momentum, not only does the trapping time decreases but also

the trend of how the trapping time depends on the effective radius of the dot

changes. In particular, as the dot radius increases, the trapping time

increases for m<3 but decreases for m > 3. The trapping time however always

decreases upon increasing the potential height. It is also found that the wave

functions corresponding to the states of larger trapping times or higher m

are more localized in space.

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References

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Published

17-07-2018

How to Cite

[1]
N. T. T. Nguyen, “Trapping electrons in a circular graphene quantum dot with Gaussian potential”, Comm. Phys., vol. 28, no. 1, p. 51, Jul. 2018.

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Section

Papers
Received 16-01-2018
Accepted 14-03-2018
Published 17-07-2018

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