Demonstration of half-metallicity in fermi-level-tuned Heusler alloy Co2FeAl0.5Si0.5 at room temperature.
Fermi level tuning has been successfully demonstrated in Co-based full-Heusler alloy Co(2)FeAl(0.5)Si(0.5) (CFAS). The half-metallic band gap of CFAS was proved by the behavior of differential conductance of CFAS/(MgAl(2))O(x)/CoFe magnetic tunneling junctions with an unexplored crystalline (MgAl(2))O(x) barrier. CFAS exhibits the highest effective spin polarization (P_{eff}) at 300 K and the weakest temperature dependence of P_{eff} among all known half metals. Further study shows that P_{eff} of CFAS decays with increasing temperature (T) following T;{3/2} law perfectly, which indicates that the depolarization of CFAS is determined by spin wave excitation only.
Shan
R
R
Magnetic Materials Center, National Institute for Materials Science (NIMS), Tsukuba, 305-0047, Japan.
Sukegawa
H
H
Wang
W H
WH
Kodzuka
M
M
Furubayashi
T
T
Ohkubo
T
T
Mitani
S
S
Inomata
K
K
Hono
K
K