Magnetic properties and giant magnetoimpedance effect of FINEMET/Fe50Pt50 composite ribbons

Magnetic field detection utilizing soft magnetic ribbons and a rectangular solenoid

“…(c) the magnetization curve of the magnetic ribbon of 3 mm × 30 mm × 0.022 mm along the ribbon length direction measured with the magnetic performance measurement system; (d) µ L of magnetic ribbon of 3 mm × 30 mm × 0.022 mm along the ribbon length direction as a function of H. as exhibited in figures 2(e) and (f). The phenomenon that both ∆L/L and ∆Z/Z of proposed sensors decline with H monotonically is similar to that of the planar magnetic inductive sensors [1,21,28] and GMI sensors [5,32,33]. The reason is that the easy magnetization axis is along the ribbon length direction and µ L decreases monotonically with H due to the magnetic domain wall movement and domain rotation.…”

“…where, δ m is the skin depth of soft magnetic ribbons, L m−dc is the solenoid DC and low-frequency inductance, expressed as [27] L m−dc (µ L ) = µ 0 µ L N 2 w m t c l r (5) where, µ 0 is the vacuum permeability, µ L is the soft magnetic ribbon longitudinal permeability, and l r are the turns and length of the solenoid, w m and t c is the width and thickness of the magnetic core.…”

“…The proposed magnetic sensor possesses the advantage of detecting biological electromagnetic signals, decreasing the Joule heat loss and power consumption [29]. (5) The rectangular solenoid is extremely compatible with microfabrication manufacturing. Therefore, the proposed prototype is exceedingly expected to manufacture high-sensitivity micromagnetic sensors.…”

“…In order to achieve notable impedance variation for planar GMI ribbon sensors, the skin depth ought to be approximately equal to the magnetic ribbon thickness, which leads to the excitation frequency having to be more than the order of MHz. The Fe 50 Pt 50 alloy was selected as the coating layer deposited on FINEMET ribbons, and (∆Z/Z) max was 122% at 1.4 MHz [5]. The maximum GMI ratio of sandwiched multilayer ([Py(100 nm)/Ti(6 nm)] 4 /Cu(400 nm)/[Ti(6 nm)/Py (100 nm)] 4 ) was obtained as 350% at 27 MHz [35].…”

“…Soft magnetic materials with high permeability are extensively applied to the development and investigation of highsensitivity magnetic sensors [1][2][3]. The magnetic sensors based on the giant magneto-impedance (GMI) effect utilize the excellent properties of soft magnetic materials whose permeability varies substantially with the magnetic field [4][5][6]. For the conventional GMI magnetic sensors, the soft magnetic materials are directly connected with the alternating current (AC), and their impedance significantly varies with the external magnetic field [7].…”