Magnetic Properties and Structural Study of Ni-Co/Cu Multilayers Prepared by Electrodeposition Method

Document Type : Research Paper

Authors

1 Department of Physics, Payame Noor University, P. O. Box 19395-3697, Tehran, Iran

2 Department of Nano Physics, Malekashtar University of Technology, Shahinshahr, Esfahan, Iran

3 Young Researchers and Elite Club, Arak Branch, Islamic Azad University, Arak, Iran

10.7508/jns.2015.03.010

Abstract

Ni-Co/Cu multilayers have been grown by electrodeposition method from a single electrolyte (based on Ni(SO4).6H2O, Co(SO4).7H2O, Cu(SO4) and H3BO3) using galvanostatic control on titanium sublayers. The X-ray diffraction (XRD) patterns confirmed the multilayered structure with the nanometer thicknesses. Also, electron diffraction x-ray (EDX)  analysis confirmed the purity of deposited samples. The morphology of the samples was estimated by scanning electron microscope (SEM). Magnetoresistance (MR) measurements were carried out at room temperature for the Ni-Co/Cu multilayers by measuring the resistivity in a magnetic fields varying between ±6kOe as a function of the Ni-Co and Cu layer thicknesses; (1 dCu(nm) 4 and 3 dNi-Cu(nm) 5). The Maximum value of giant magnetoresistance (GMR) was obtained when the Ni-Co and Cu thicknesses were 4.0nm and 4.0nm respectively. The hysteresis loop of the samples at room temperature was studied using an alternating gradient force magnetometer (AGFM). Finally, the temperature dependence of magnetization for Ni-Co/Cu multilayers; (dNi-Cu(4nm)/dCu(2nm) and dNi-Cu(3nm)/dCu(3nm)) measured by Faraday balance and decreasing the magnetization with increasing the temperature discussed according to electron scattering due to spin fluctuation.

Keywords


[1] M. N. Baibich, J. M. Broto, A. Fert, F. Petroff, P. Eitenne, G. Creuzet, A. Freiderich and J. Chazelas. Phys. Rev. Lett 61 (1988) 2472-2480.
[2] M. Angelakeris, E. T. Papaioannou, P. Poulopoulos, O. Valassiades and N. K. Flevaris. Sens. Acta. A 106 (2003) 91-97.
[3] C. A. Ross, Ann. Rev. Mater. Sci 24 (1994) 159-165.
[4] I. Bakonyi and L. Peter. Progr. Mater. Sci 55 (2010) 107-112.
[5] M. Jafari Fesharaki, L. Peter T. Schuchknecht, D. Rafaja, J. Degi, L. Pogany, K. Neurohur, E. Szeles, G. Nabiyouni and I. Bakonyi. J. Electrochem. Soc 159 (2012) D162-D171.
[6] E. Hiroto, H. Sakakima and K. Inomato, “Giant Magnetoresistance Devices” 2001, Springer.
[7] Y. Fujii, “In Metallic Superlattices; Studies in physical and theoretical chemistry” vol 49 Elsevier, Amesterdam (1987).
[8] B. Deiny, U. S. Sperious, S. S. P. Parkin and B. A. Gurney, Phys. Rev. B, 43 (1991) 1297-1303.
[9] B. G. Toth, L. Peter , J. Degi, A. Revesz, D. Oszetzky, G. Molnar and I. Bakonyi. Electrochim. Acta 49 (2013) 122-129.
[10]  N. Rajasekaran, S. Mohan, J. Arout Chelvane and R. Jagannathan, J. Magn. Magn. Mater 324 (2012) 2983-2988.
[11] H. Hasegawa, Phys. Rev. B, 47 (1993) 15080-15085.