Localized Magnetic States in Three Dimensional Dirac Solids

Abstract

Formation of localized magnetic states in a metallic host is a classic problem of condensed matter physics formalized by P. W. Anderson within the so called single impurity Anderson model (SIAM). The general picture in a host of a simple one-band metal is that a large Hubbard U in the impurity orbital is pre-requisite for the formation of localized magnetic states. In recent years three dimensional (3D) Dirac solids have emerged the hallmark of which is strong spin-orbit interaction. In this work we show that such a strong spin-orbit interaction allows to form localized magnetic states even with small values of Hubbard U . This opens up the fascinating possibility of forming magnetic states with s or p orbital impurities -a different from traditional paradigms of d or f orbital based magnetic moments.

Formation of localized magnetic states in a large-spin Fermi system

“…Therefore, the impurity magnetic moment can be tuned by varying the size of the metal clusters and thereby adjusting their energy gaps. The AIM has also been extended to Dirac systems 23,24 . A special feature of Dirac systems is that the energy band structure demonstrates a linear dispersion relation at the Dirac points, which differs from the parabolic band structure of an ordinary metal.…”

“…Due to the anomalous broadening of adatom local electronic states in graphene, the local magnetic moment is formed more easily in graphene than in metals 23 . Moreover, the study of three dimensional Dirac solid suggests that spin-orbit coupling facilitates the formation of localized magnetic states 24 . In addition, the AIM has recently been extended to twodimensional semiconductors with Dirac-like dispersion, and this system facilitates the formation of local magnetic moments 25 .…”