Title :
Spin-dependent tunneling in double tunnel junctions with a discontinuous intermediate layer
Author :
Saito, Y. ; Nakajima, K. ; Tanaka, K. ; Inomata, K.
Author_Institution :
R&D Center, Toshiba Corp., Kawasaki, Japan
fDate :
9/1/1999 12:00:00 AM
Abstract :
Detailed characteristics and tunnel magnetoresistance (TMR) properties of the double tunnel junctions (DTJs) through Co80Pt20 hard magnetic particles were investigated in the low barrier height regime. Significant difference in current distribution effect was observed in DTJs through discontinuous particles. No geometrically enhanced magnetoresistance occurs in the cross-shaped 0.01 mm2 size junctions when the measured junction resistance is 10 times smaller than the electrode resistance due to the decrease in the effective junction area in DTJs with discontinuous ferromagnetic particles. Moreover, temperature independent TMR ratio and enhancement of the TMR ratio in a low bias voltage regime were observed in DTJs through Co80Pt20 hard magnetic particles in low barrier height regime
Keywords :
cobalt alloys; ferromagnetic materials; magnetic multilayers; magnetic particles; magnetoresistance; permanent magnets; platinum alloys; tunnelling; Co80Pt20; Co80Pt20 hard magnetic particles; current distribution effect; discontinuous ferromagnetic particles; discontinuous intermediate layer; discontinuous particles; double tunnel junctions; effective junction area; electrode resistance; junction resistance; low barrier height regime; low bias voltage regime; spin-dependent tunneling; tunnel magnetoresistance; Area measurement; Current distribution; Electrical resistance measurement; Enhanced magnetoresistance; Magnetic particles; Magnetic properties; Magnetic tunneling; Particle measurements; Size measurement; Tunneling magnetoresistance;
Journal_Title :
Magnetics, IEEE Transactions on
