ANALYSIS OF THE ELECTRONIC STRUCTURE OF AN ELECTRICALLY INDUCED QUANTUM DOT IN THE EXTERNAL MAGNETIC FIELD
Abstract
Numerical modeling of the electronic structure of a quantum dot, induced by an electric field of a nanosized disc-shaped gate, is carried out in the presence of external magnetic field. The dependences of an electronic energy spectrum on electric and magnetic fields are calculated using the finite element method. It has been found that a series of anti-crossing points for electronic levels takes place at relatively small magnetic fields. The existence of groups of close-energy levels (electronic shells) has been found. It has been shown that despite the essential distinction of the gate potential from the parabolic one, a model of a near-surface anisotropic harmonic oscillator can be effectively used for a qualitative description of the electronic structure of the electrically induced quantum dot. With the use of this model, the evolution of energy spectrum and wave function structure with magnetic and electric fields is described. In particular, the anisotropic oscillator model allows to predict anti-crossing points of electronic levels in external fields, as well as quasi-degeneracy of states having different values of the angular momentum projection.
About the Authors
E. A. Levchuk
Belarusian State University,
Belarus
Belarus
Postgraduate
L. F. Makarenko
Belarusian State University,
Belarus
Belarus
Ph. D. (Physics and Mathe ma-tics), Assistant Professor, Assistant Professor of the Mathematical Modeling and Control Department
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