Shot noise in magnetic tunnel junctions

November 3 2011
Types d’événements
Séminaire SPEC
Tomonori Arakawa
SPEC Salle Itzykson, Bât.774
03/11/2011
from 14:30

The resistance of a magnetic tunnel junction (MTJ) depends on the
relative magnetization of the ferromagnetic layers such that it is low
in the parallel (P) configuration while it is high in the anti-parallel
(AP) one. The coherent tunneling is theoretically predicted to play a
central role in MTJs with the crystalline MgO barriers.
In this presentation, we report the shot noise measurement in
well-crystalline CoFeB/MgO/CoFeB-based MTJs with the increased
experimental accuracy. We observed reduced Fano factor (F~0.91) in P
configuration, while F in AP configuration was close to 1. Moreover,
this reduction is independent to the sample temperature and the
magnetic field.

Institute for Chemical Research, Kyoto University