2012/11/30 by Milena Filipovic, Milena Filipović, Cecilia Holmqvist +2
Engineering · Materials Science · Physics and Astronomy · #Condensed matter physics #Electron #Larmor precession #Magnetic field #Magnetism in coordination complexes #Magnetization #Magnetization dynamics #Molecular Junctions and Nanostructures #Physics #Precession #Quantum and electron transport phenomena #Quantum mechanics #Quantum tunnelling #Spin (aerodynamics) #Spin polarization #Spin-transfer torque #Spins #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.87.045426
published as Physical Review B 87, 045426 (2013) · 11 pages, 9 figures, final version including corrections to published article
openalex publication_date 2013/01/28 · arxiv created 2013/07/22 · arxiv updated 2013/07/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study time-dependent electronic and spin transport through an electronic level connected to two leads and coupled with a single-molecule magnet via exchange interaction. The molecular spin is treated as a classical variable and precesses around an external magnetic field. We derive expressions for charge and spin currents by means of the Keldysh nonequilibrium Green's functions technique in linear order with respect to the time-dependent magnetic field created by this precession. The coupling between the electronic spins and the magnetization dynamics of the molecule creates inelastic tunneling processes which contribute to the spin currents. The inelastic spin currents, in turn, generate a spin-transfer torque acting on the molecular spin. This back-action includes a contribution to the Gilbert damping and a modification of the precession frequency. The Gilbert damping coefficient can be controlled by the bias and gate voltages or via the external magnetic field and has a nonmonotonic dependence on the tunneling rates.