Spin-flip inelastic electron tunneling spectroscopy in atomic chains

Abstract

We present a theoretical study of the spin transport properties of monoatomic magnetic chains with a focus on the spectroscopical features of the I - V curve associated with spin-flip processes. Our calculations are based on the s-d model for magnetism with the electron transport treated at the level of the nonequilibrium Green's function formalism. Inelastic spin-flip scattering processes are introduced perturbatively via the first Born approximation, and an expression for the associated self-energy is derived. The computational method is then applied to describe the I - V characteristics and its derivatives of one-dimensional chains of Mn atoms, and the results are then compared to available experimental data. We find a qualitative and quantitative agreement between the calculated and the experimental conductance spectra. Significantly we are able to describe the relative intensities of the spin excitation features in the I - V curve, by means of a careful analysis of the spin transition selection rules associated with the atomic chains.