Spin-orbit coupling and Kondo resonance in Co adatom on Cu(100) surface: DFT+ED study

TL;DR

This study combines DFT and exact diagonalization to investigate how spin-orbit coupling influences Kondo resonance in a Co adatom on Cu(100), revealing its crucial role in forming Kondo singlets.

Contribution

It demonstrates the importance of spin-orbit coupling in the formation of Kondo resonance in a multi-orbital impurity system using combined DFT+ED methods.

Findings

Kondo resonance appears with spin-orbit coupling included.

Differential conductance matches STM measurements.

Spin-orbit coupling is essential for Kondo singlet formation.

Abstract

We report density functional theory plus exact diagonalization of the multi-orbital Anderson impurity model calculations for the Co adatom on the top of Cu(001) surface. For the Co atom $d$-shell occupation $n_d \approx$ 8, a singlet many-body ground state and Kondo resonance are found, when the spin-orbit coupling is included in the calculations. The differential conductance is evaluated in a good agreement with the scanning tuneling microscopy measurements. The results illustrate the essential role which the spin-orbit coupling is playing in a formation of Kondo singlet for the multi-orbital impurity in low dimensions.