Magnetoresistance characteristics of (NiFe/Ni/NiFe)/Cu multilayers

By inserting two or three layers of NiFe at the interfaces of Ni/Cu multilayers, the magnetoresistance properties of Ni/Cu could be appreciably improved. 50 Oe of saturation magnetic field and 6% of magnetoresistance were obtained in glass/Cu(50 Å)[NiFe(7 Å)Ni(6 Å)NiFe(7 Å)/Cu(20 Å)]₂₀ structured multilayers. 25 Oe of saturation magnetic field and 4.5% of magnetoresistance were obtained in 4° tilt-cut Si(111)/NiFe(50 Å)[NiFe(7 Å)Ni(6 Å)NiFe(7 Å)/Cu(20 Å)]₁₀. Almost negligible hysteresis was shown in both structures, which turned out to be much advantageous in obtaining magnetoresistance signals under ac magnetic field