Generalized Landauer-Büttiker equations in multiprobe conductors: Application to magneto-transport in magnetic nanowires

LUCAS J. FERNÁNDEZ

La Falda - Córdoba

Encuentro; XII Encuentro ?Superficies y Materiales Nanoestructurados 2012"; 2012

The electronic transport spin-dependent in metals has had a great progress in the last decades. The pioneering ideas was introduced by Mott in the two band model [1]. It proposes that each orientation of the electronic spin conduces the current as an independent channel and the magnetic field produces a splitting in the density of states d that it is very dependent of the spin. This ideas were taken by Fert for the development of a semi classical simple model known as two resistors model. It explains the phenomenon of giant magnetoresistance in ferromagnetic metals with a abrupt magneticinterface [2]. The two resistors model considers that each orientation of the spin undergoes a scattering whose magnitude varies as it is aligned or anti-aligned with the local magnetic field. Also, it takes into account the existence of processes of mixing of the two orientations of the spin in a lengththat determines the size of the system to be analyzed [3].In this work we present a description based in the D?Amato-Pastawski model that allows us study the transport using the Landauer-Büttiker formalism and incorporate the effects of the decoherence in the problem. We present the calculation of the chemical potentials and currents along the system usingthis novel approach in coincidence with the results obtained by Valet and Fert using the Boltzmann equation. The advantage of our description is it enables to describe the quantum interference effects that appear when the interface is not abrupt.[1] N. F. Mott. Proc. R. Soc. (London) 153 699 (1936).[2] A. Fert. Rev. Mod. Phys. 80 1517 (2008)[3] T. Valet and A. Fert. Phys. Rev. B 48 7099 (1993)