Spin-flip inelastic electron spectroscopy

Abstract

Recent experimental advances in scanning tunneling microscopy make the measurement of the conductance spectra of isolated and magnetically coupled atoms on nonmagnetic substrates possible. The typical example is that of Co, Fe or Mn atoms deposited on CuN. Notably, the conductance spectra are characterized by a competition between the Kondo effect and spin-flip inelastic electron tunneling. In this thesis, the interaction between electron spins and local spins is treated at the level of the non-equilibrium Green's function scheme for electron transport. It will be demonstrated that the Green's function method is capable of a semi-quantitative description of the competition between Kondo resonances and spin-flip inelastic electron tunneling at a computational cost significantly lower than that of other approaches. The theory is also extended to explain spin and non-spin polarized STM probes and to cases when the spin-system is driven out of equilibrium.