Valence fluctuations and Kondo resonance in Co adatom on Cu.sub.2./sub.N/Cu(100) surface: DFT + ED study

0549622 - FZÚ 2022 RIV GB eng J - Článek v odborném periodiku
Tchaplianka, Maxim - Shick, Alexander - Lichtenstein, A.I.
Valence fluctuations and Kondo resonance in Co adatom on Cu₂N/Cu(100) surface: DFT + ED study.
New Journal of Physics. Roč. 23, č. 10 (2021), č. článku 103037. ISSN 1367-2630. E-ISSN 1367-2630
Grant CEP: GA ČR GA18-06240S; GA MŠMT(CZ) EF16_019/0000760
Grant ostatní: OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institucionální podpora: RVO:68378271
Klíčová slova: electron correlation effects * spin - orbit coupling * density functional theory * STM * XMCD
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.)
Impakt faktor: 3.716, rok: 2021
Způsob publikování: Open access

We report density functional theory plus exact diagonalization of the multi-orbital Anderson impurity model calculations including the spin-orbit coupling for the Co adatom on the top of Cu2N/Cu(001) surface. It is found that experimentally observed zero-bias peak in differential conductance can occur for quasi-degenerate many-body solution representing a mixed valence state of the Co adatom with the non-integer d manifold occupation of 7.4. Estimated 5 meV inelastic step energy is in a quantitative agreement with the experimental scanning tunnelling spectroscopy value of 6 meV. We find the non-zero spin and orbital magnetic moments in the applied magnetic field, in a reasonable agreement with the x-ray magnetic circular dichroism data. The presence of large orbital magnetic moment was not considered in previous spin-only theoretical interpretations, and can unravel complexity of the physics behind the experimental spectra for Co and other adatoms on Cu2N/Cu(001) surface.
Trvalý link: http://hdl.handle.net/11104/0325593