摘要 |
A resonator for use in a marker in a magnetomechanical electronic article surveillance system is formed by a planar strip of an amorphous magnetostrictive alloy having a composition FeaCobNicSixByMz wherein a, b, c, x, y, and z are at % and a+b+c+x+y+z=100, a+b+c>75, a>15, b<20, c>5 and z<3, wherein M is at least one element selected from the group consisting of C, P, Ge, Nb, Mo, Cr and Mn, the amorphous magnetostrictive alloy having a resonant frequency fr which is a minimum at a field strength Hmin and having a linear B-H loop up to at least a field strength which is about 0.8 Hmin and a uniaxial anisotropy perpendicular to the plane of the strip with an anisotropy field strength Hk which is at least as large as Hmin and, when driven by an alternating signal burst in the presence of a bias field Hb, producing a signal at the resonant frequency having an amplitude which is a minimum of approximately 50% of a maximum obtainable amplitude relative to the bias field Hb in a range of Hb between 0 and 10 Oe.
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