Dipolar interactions and anisotropic magnetoresistance in metallic granular systems

• Type: Article in International Scientific Journal
• Date: 2002

Authors

Lopes, JV (Author) Other; dos Santos, JMBL (Author) FCUP; Pogorelov, YG (Author) FCUP

Journal

Title: Physical Review B - Condensed Matter and Materials Physics

Vol. 66

Pages: 1-9

ISSN: 1098-0121

Publisher: American Physical Society

Indexing

ISI Web of Knowledge - 3 Citations

Scopus - 0 Citations

Scientific classification

FOS: Natural sciences > Physical sciences

Other information

Authenticus ID: P-000-NJE

DOI: 10.1103/physrevb.66.064416

Abstract (EN): We revisit the theory of magnetoresistance for a system of nanoscopic magnetic granules in a metallic matrix. Using a simple model for the spin-dependent perturbation potential of the granules, we solve the Boltzmann equation for the spin-dependent components of the nonequilibrium electronic distribution function. For typical values of the geometric parameters in granular systems, we find a peculiar structure of the distribution function of conduction electrons, which is at variance with the two-current model of conduction in inhomogeneous systems. Our treatment explicitly includes the effects of dipolar correlations yielding a magnetoresistance ratio which contains, in addition to the term proportional to the square of uniform magnetization <mu>, a weak anisotropic contribution depending on the angle between electric and magnetic fields, and arising from the anisotropic character of dipolar interactions.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9