Emergent spin filter at the interface between ferromagnetic and insulating layered oxides.
We report a strong effect of interface-induced magnetization on the transport properties of magnetic tunnel junctions consisting of ferromagnetic manganite La0.7Ca0.3MnO3 and insulating cuprate PrBa2Cu3O7. Contrary to the typically observed steady increase of the tunnel magnetoresistance with decreasing temperature, this system exhibits a sudden anomalous decrease at low temperatures. Interestingly, this anomalous behavior can be attributed to the competition between the positive spin polarization of the manganite contacts and the negative spin-filter effect from the interface-induced Cu magnetization.
Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
Yaohua
Y
Liu
GFMC, Departamento de Fisica Aplicada III, Universidad Complutense de Madrid, Campus Moncloa, ES-28040 Madrid, Spain.
F A
FA
Cuellar
GFMC, Departamento de Fisica Aplicada III, Universidad Complutense de Madrid, Campus Moncloa, ES-28040 Madrid, Spain.
Z
Z
Sefrioui
Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
J W
JW
Freeland
Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
M R
MR
Fitzsimmons
GFMC, Departamento de Fisica Aplicada III, Universidad Complutense de Madrid, Campus Moncloa, ES-28040 Madrid, Spain.
C
C
Leon
GFMC, Departamento de Fisica Aplicada III, Universidad Complutense de Madrid, Campus Moncloa, ES-28040 Madrid, Spain.
J
J
Santamaria
Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
S G E
SG
te Velthuis