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Minimal length implications on the Hartree-Fock theory

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 نشر من قبل Mohammad Mohammadi Sabet
 تاريخ النشر 2021
  مجال البحث فيزياء
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Hartree-Fock approximation suffers from two inabilities including i) the divergence of electron Fermi velocity , and ii) existence of bandwidth not con?rfimed experimentally. Here, we study the effects of minimal length on the ground state energy of the electron gas in the Hartree-Fock approximation. Our results indicate that considering some mathematical terms, similar to those of used for the minimal length correction to the Hamiltonian of system, can eliminate the weaknesses of Hartree-Fock approximation. These corrections, on the other hand, can be considered as relativistic corrections of electron in solids. Physically, it is obtained that electrons in metals can be employed to test the quantum gravity scenario, if the value of its parameter (?$beta$) lies within the range of 2 to 10, depending on the used metal. Indeed, the latter addresses an upper bound on ?$beta$? which is comparable with previous works meaning that these types of systems may be employed in testing quantum gravity scenarios. To overcome the in?nite Fermi velocity in Hartree-Fock method, the screening potential is used based on the Lindhard theory. We also ?nd that considering the generalized Heisenberg uncertainly leads to some additional oscillating terms in the Friedel oscillations.

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