Local magnetic moment formation and Kondo screening in the half-filled single-band Hubbard model

We study the formation of local magnetic moments in the strongly correlated Hubbard model within dynamical mean-field theory and associate peculiarities of the temperature dependence of local charge chi c and spin chi s susceptibilities with different stages of local moment formation. The local maximum of the temperature dependence of the charge susceptibility chi c is associated with the beginning of local magnetic moment formation, while the minimum of the susceptibility chi c and double occupation, as well as the low-temperature boundary of the plateau of the effective local magnetic moment mu 2eff = T chi s temperature dependence are connected with the full formation of local moments. We also obtain the interaction dependence of the Kondo temperature TK, which is compared to the fingerprint criterion of Chalupa et al. [Phys. Rev. Lett. 126, 056403 (2021)]. Near the Mott transition the two criteria coincide, while further away from the Mott transition the fingerprint criterion somewhat overestimates the Kondo temperature. The relation of the observed features to the behavior of eigenvectors/eigenvalues of fermionic frequency-resolved charge susceptibility and divergences of irreducible vertices is discussed.

Automated summary

This study investigates the formation of local magnetic moments in the strongly correlated Hubbard model using dynamical mean-field theory, linking the temperature dependence of local charge and spin susceptibilities to different stages of local moment formation. The relationship between the Kondo temperature and the fingerprint criterion is discussed, with similarities near the Mott transition and slight discrepancies further away. Additionally, the behavior of eigenvectors/eigenvalues of fermionic frequency-resolved charge susceptibility and divergences of irreducible vertices is considered in relation to the observed features.