TY - JOUR
T1 - Enhanced tunnel magnetoresistance in a spinel oxide barrier with cation-site disorder
AU - Sukegawa, Hiroaki
AU - Miura, Yoshio
AU - Muramoto, Shingo
AU - Mitani, Seiji
AU - Niizeki, Tomohiko
AU - Ohkubo, Tadakatsu
AU - Abe, Kazutaka
AU - Shirai, Masafumi
AU - Inomata, Koichiro
AU - Hono, Kazuhiro
PY - 2012/11/2
Y1 - 2012/11/2
N2 - We report enhanced tunnel magnetoresistance (TMR) ratios of 188% (308%) at room temperature and 328% (479%) at 15 K for cation-site-disordered MgAl 2O 4-barrier magnetic tunnel junctions (MTJs) with Fe (Fe 0.5Co 0.5 alloy) electrodes, which exceed the TMR ratios theoretically calculated and experimentally observed for ordered spinel barriers. The enhancement of TMR ratios is attributed to the suppression of the so-called band-folding effect in ordered spinel MTJs. First-principles calculations describe a dominant role of the oxygen sublattice for spin-dependent coherent tunneling, suggesting a mechanism of coherent tunneling occurring even in the disordered systems.
AB - We report enhanced tunnel magnetoresistance (TMR) ratios of 188% (308%) at room temperature and 328% (479%) at 15 K for cation-site-disordered MgAl 2O 4-barrier magnetic tunnel junctions (MTJs) with Fe (Fe 0.5Co 0.5 alloy) electrodes, which exceed the TMR ratios theoretically calculated and experimentally observed for ordered spinel barriers. The enhancement of TMR ratios is attributed to the suppression of the so-called band-folding effect in ordered spinel MTJs. First-principles calculations describe a dominant role of the oxygen sublattice for spin-dependent coherent tunneling, suggesting a mechanism of coherent tunneling occurring even in the disordered systems.
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U2 - 10.1103/PhysRevB.86.184401
DO - 10.1103/PhysRevB.86.184401
M3 - Article
AN - SCOPUS:84869032858
VL - 86
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
SN - 0163-1829
IS - 18
M1 - 184401
ER -