High-Quality Ni-Fe/Cu Multilayer Films with Antiferromagnetic Coupling

Abstract

We report structural and magnetic properties of Ni83Fe17/Cu multilayer films with various buffer layer and sublayer thicknesses of copper dcu and Permalloy dp y deposited by face-to-face sputtering. The following features prove a good quality of our films: a well-layered structure, complete antiferromagnetic coupling with a low coupling strength (2 x 10 -5 J/m2 for dcu = 1 nm and 10 -5 J/m2 for dc" = 2.1 nm) and a low coercive field which make them attractive for possible applications as giant magnetoresistance sensors.PACS numbers: 76.50.+g, 75.50.Tt Recently, there has been a considerable interest in magnetic and magnetotransport properties of Py/Cu and Py/Au (Py = Permalloy) multilayers (Mis) [1][2][3][4][5][6]. Much of this interest has focused on developing Mls with the highest possible giant magnetoresistance (GMR), a low antiferromagnetic coupling strength (JAF) with a high fraction of antiferromagnetically (AF) coupled regions FAF = (1 -MR/Ms) (MR, Ms are the remanence and saturation magnetization) and a low coercive field H. Since the results obtained by several authors with the use of different deposition techniques vary [1][2][3][4][5], the magnetic properties of Py/Cu Mls seem to be very sensitive to the deposition and growth conditions. In the present paper we report on magnetic and structural properties of Si(100)/B/(Py/Cu)N Mis (B -buffer layer with a thickness dB, Py = Ni83Fe17, N -number of periods) with various sublayers thicknesses of Cu dk u ) and Permalloy (dPy ) obtained by the face-to-face sputtering technique [7]. The magnetic properties of the samples were determined from the hysteresis loops measured with a vibrating sample magnetometer (VSM) and magneto-optical Kerr effect (MOKE). The well-defined (277)

Giant Magnetoresistance in Permalloy/Copper Multilayers

“…magnetically inactive layer -MIL) together with the ferromagnetic one with reduced magnetization (relative to Py magnetization). The MIL thickness determined from our magnetic moment measurements was found to be of about 0.6 nm [2]. This value agrees well with dp y = 0.5 nm for which GMR = O (Fig.…”

Magnetic Anisotropy and Magnetostriction Oscillations in Magnetic Multilayers

“…The samples were prepared by double face-to-face sputtering method [8] on glass substrates. The thickness of permalloy layer was almost constant equal to 2 nm and the thickness of Cu layer varied from 1.4 nm to 2.5 nm.…”