Summary: Mesoscopic anisotropic magnetoconductance fluctuations in ferromagnets
Shaffique Adam, Markus Kindermann, Saar Rahav, and Piet W. Brouwer
Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853-2501, USA
Received 9 May 2006; published 8 June 2006
The conductance of a ferromagnetic particle depends on the relative orientation of the magnetization with
respect to the direction of current flow. This phenomenon is known as "anisotropic magnetoresistance." Quan-
tum interference leads to an additional random dependence of the conductance on the magnetization direction.
These "mesoscopic anisotropic magnetoresistance fluctuations" are caused by the interplay of random impurity
scattering and spin-orbit scattering, which couples the electron motion to the exchange field in the ferromagnet.
We report a calculation of the dependence of the conductance autocorrelation function on the rotation angle of
the magnetization direction.
DOI: 10.1103/PhysRevB.73.212408 PACS number s : 75.75. a, 72.15. v, 72.25. b, 73.22. f
One hallmark of phase-coherent transport is the phenom-
enon of "universal conductance fluctuations," random, but
reproducible variations in a sample's conductance as a func-
tion of the applied magnetic field or the Fermi energy.1­5 The
magnitude of the conductance fluctuations is of order unity,
in units of the conductance quantum e2
/h, and does not de-
pend on specific sample properties, such as the impurity con-

Source: Adam, Shaffique - Condensed Matter Theory Center, University of Maryland at College Park

Collections: Physics