Spin-orbit coupling and Kondo resonance in the Co adatom on the Cu(100) surface: DFT plus exact diagonalization study

We report density functional theory plus exact diagonalization of the multiorbital Anderson impurity model calculations for the Co adatom on the top of a Cu(001) surface. For the Co atom d-shell occupation nd approximate to 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 good agreement with the scanning tunneling microscopy measurements. The results illustrate the essential role which the spin-orbit coupling is playing in the formation of a Kondo singlet for the multiorbital impurity in low dimensions.

Automated summary

We present density functional theory plus exact diagonalization calculations of the multiorbital Anderson impurity model for the Co adatom on Cu(001) surface. The results show the existence of a singlet many-body ground state and Kondo resonance for the Co atom with an approximate d-shell occupation of nd ≈ 8 when the spin-orbit coupling is included. The differential conductance obtained from the calculations agrees well with scanning tunneling microscopy measurements. These findings highlight the essential role of spin-orbit coupling in the formation of a Kondo singlet for a multiorbital impurity in low dimensions.