TY - JOUR AU - dos Santos Dias, Manuel AU - Schweflinghaus, B. AU - Blügel, S. AU - Lounis, S. TI - Relativistic dynamical spin excitations of magnetic adatoms JO - Physical review / B VL - 91 IS - 7 SN - 1098-0121 CY - College Park, Md. PB - APS M1 - FZJ-2015-02795 SP - 075405 PY - 2015 AB - We present a first-principles theory of dynamical spin excitations in the presence of spin-orbit coupling. The broken global spin rotational invariance leads to a new sum rule. We explore the competition between the magnetic anisotropy energy and the external magnetic field, as well as the role of electron-hole excitations, through calculations for 3d-metal adatoms on the Cu(111) surface. The spin excitation resonance energy and lifetime display nontrivial behavior, establishing the strong impact of relativistic effects. We legitimate the use of the Landau-Lifshitz-Gilbert equation down to the atomic limit, but with parameters that differ from a stationary theory. LB - PUB:(DE-HGF)16 UR - <Go to ISI:>//WOS:000349247900003 DO - DOI:10.1103/PhysRevB.91.075405 UR - https://juser.fz-juelich.de/record/189765 ER -