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arXiv · 2410.22538

Informational analysis of the confinement of an electron in an asymmetric double quantum dot

Abstract

A quasi-unidimensional one-electron double quantum dot is studied within the framework of Shannon informational entropy. Its confinement potential, which is described by an asymmetric harmonic-gaussian function, consists of two wells separated by a potential barrier, and the asymmetry of the potential in respect to the center of the barrier is parameterized by $x_0$. In this work we employ Shannon informational entropy as a tool to investigate changes in the electronic confinement resulting from the modifications in the degree of asymmetry $x_0$. In particular, we notice that Shannon entropy turns out to be very sensitive to the change from the symmetric to the antisymmetric regime. Moreover, we show that Shannon entropy as a function of $x_0$ for an electronic excited state displays an irregular behavior whenever the state energy is in the vicinity of a local extreme (a maximum or a minimum); connected with this we observe an oscillatory behavior of the energy of the excited states as a function of $x_0$.

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BibTeXRIS

W. S. Nascimento, A. M. Maniero, F. V. Prudente, C. R. de Carvalho, Ginette Jalbert. 2024-12-26. Informational analysis of the confinement of an electron in an asymmetric double quantum dot. https://doi.org/10.1016/j.physb.2024.416769

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