ИСТИНА

In this work, the induced electric dipole moment of ferromagnetic microwires dependent on the wire magnetic structure is investigated with the aim of sensing applications. The wire behaves as micro antenna exhibiting a resonance at half wavelength condition. At the vicinity of the resonance the wire polarization is sensitive to all the losses including magnetic losses. The transfer mechanism is based on the magnetoimpedance effect (MI) which requires a specific magnetic structure of a helical type. We demonstrate that scattering from a ferromagnetic microwire showing large MI effect at microwaves can be modulated with a low frequency magnetic field and the amplitude of this modulation near the antenna resonance can sensitively change in the presence of the external stimuli such as a dc magnetic field. The modelling is based on solving the scattering problem from a cylindrical wire with the impedance boundary conditions. The modelling results agree well with the experimental data.