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Current issue   Ukr. J. Phys. 2016, Vol. 61, N 9, p.759-773
https://doi.org/10.15407/ujpe61.09.0759    Paper

Sobol O.O.

Taras Shevchenko National University of Kyiv
(2, Academician Glushkov Ave., Kyiv 03022, Ukraine; e-mail: sobololeks@gmail.com)

Structural Supercritical Instability of Dirac Electrons in the Field of Two Oppositely Charged Nuclei

Section: Plasmas and Gases
Original Author's Text: Ukrainian

Abstract: The Dirac equation for an electron in a finite dipole potential has been studied within the method of linear combination of atomic orbitals (LCAO). The Coulomb potential of the nuclei that compose a dipole is regularized, by considering the finite nuclear size. It is shown that if the dipole momentum reaches a certain critical value, the novel type of supercriticality occurs; namely, the wave function of the highest occupied electron bound state changes its localization from the negatively charged nucleus to the positively charged one. This phenomenon can be interpreted as a spontaneous creation of an electron-positron pair in vacuum, with each of the created particles being in the bound state with the corresponding nucleus and partially screening it.

Key words: supercritical instability, wave-function localization change, critical dipole moment, LCAO method.

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