Domain structure and magnetization process of a giant magnetoimpedance geometry FeNi/Cu/FeNi(Cu)FeNi/Cu/FeNi sensitive element

Abstract

The magnetization process and the magnetic domains of the FeNi (100 nm)/Cu (2.5 nm)/FeNi (100 nm)/Cu (480 nm)/FeNi (100 nm)/Cu (2.5 nm)/FeNi (100 nm) structure were studied. This geometry consists of two FeNi/Cu/FeNi trilayers with a thick in the direction perpendicular to the plane of the sensitive element and narrow in the direction of the flowing current Cu electrode in the centre. Ferromagnet/conductor/ferromagnet is the typical geometry of magnetoimpedance thin-film-based sensitive elements used to detect small magnetic fields. Multilayered structures were prepared by rf-sputtering in a magnetic field of 100 Oe applied perpendicular to the Cu electrode in order to induce transverse magnetic anisotropy. The magnetic measurements and magnetic domain structure observations were made in magnetic fields applied one at a time parallel or perpendicular to the Cu electrode. Different magnetization processes with non-homogeneous rotations in the first case and dominant multiple nucleation and merging of domains in the second one were observed.

Magnetoimpedance effect at the high frequency range for the thin film geometry: Numerical calculation and experiment

“…Experimentally, studies on MI have been widely performed in sheets 9 , magnetic ribbons 10-15 , wires [16][17][18][19][20][21][22][23] , and in ferromagnetic films with several structures, such as single layered [24][25][26] , multilayered 2,27-33 , and structured multilayered samples [28][29][30][33][34][35][36][37][38][39] .…”

Magnetization dynamics in nanostructures with weak/strong anisotropy

“…6,8 Since the discovery of the effect, MI has been studied in a wide variety of systems, e. g., sheets, 9 wires, [10][11][12][13][14][15][16][17][18] ribbons, [19][20][21][22][23][24] and thin films. [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39] In the particular case of films, an increasing interest has been devoted to the effect in single layered, 25,26 multilayered, [27][28][29][30][31][32] and structured multilayered thin films, 30,31,[33][34][35][36][37][38][39] since ...…”

Magnetic properties and huge magnetic impedance of permalloy/ copper/permalloy film elements

“…However, for frequencies above 150 MHz, the maximum ΔZ/Z value is higher for elements TII. Attempts of a comparison of the special features of the magnetic impedance effect for three-layer permalloy/copper/permalloy films with identical configurations of layers and a narrow central copper layer were undertaken in many experimental [4,5,7,13,14], theoretical [4,5,7], and computer modeling works [7,14,15]. Until recently, a problem solution has been complicated by the fact that not all geometrical parameters of the sensitive elements have been taken into account in the comparative studies.…”