Magnon and phonon assisted tunneling in a high-magnetoresistance tunnel junction using Co 75 Fe 25 ferromagnetic electrodes
Abstract
Magnetoelectric properties of the spin-valve-type tunnel junction of Ta(5\ nm)/Ni
79
Fe
21
(25 nm)/Ir
22
Mn
78
(10 nm)/Co
75
Fe
25
(4 nm)/Al (0.8 nm)-oxide/Co
75
Fe
25
(4 nm)/Ni
79
Fe
21
(20 nm)/Ta (5 nm) are investigated both experimentally and theoretically. It is shown that both magnon and phonon excitations contribute to the tunneling process. Moreover, we show that there are two branches of magnon with spin
S=1/2
and 3/2 respectively. The theoretical results are in good agreement with the experimental data.