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Spectral properties and the Kondo effect of cobalt adatoms on silicene

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 نشر من قبل Ireneusz Weymann
 تاريخ النشر 2017
  مجال البحث فيزياء
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In terms of the state-of-the-art first principle computational methods combined with the numerical renormalization group technique the spectroscopic properties of Co adatoms deposited on silicene are analyzed. By establishing an effective low-energy Hamiltonian based on first principle calculations, we study the behavior of the local density of states of Co adatom on external parameters, such as magnetic field and gating. It is shown that the Kondo resonance with the Kondo temperature of the order of a few Kelvins can emerge by fine-tuning the chemical potential. The evolution and splitting of the Kondo peak with external magnetic field is also analyzed. Furthermore, it is shown that the spin polarization of adatoms spectral function in the presence of magnetic field can be relatively large, and it is possible to tune the polarization and its sign by electrical means.

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