Magnetic properties and GMR of sputtered permalloy/Au multilayers

We report on structural, magnetic, and GMR properties of permalloy/Au multi layers where permalloy = Ni83Fe17, deposited by face-to-face sputtering ont o Si(111) substrate. X-ray diffraction studies confirmed a good structural quality of our multilayers. The samples were characterised with vibrating s ample magnetometer, longitudinal magnetooptical Kerr effect and giant magne toresistance measurements. It was determined that our multilayers are magne tically very soft with H-c approximate to 1 Oe and show uniaxial anisotropy with H-K approximate to 5 Oe. For gold sublayer thickness d(Au) close to 1 .1 nm the antiferromagnetic coupling is present in very narrow Au thickness range (approximate to 0.2 nm). Despite a good structural quality of sample s relatively small giant magnetoresistance value (1.2% at loom temperature) was found. It is due to non-perfect aniferromagnetic coupling caused by pi nholes.