S. Nikitov

Publications (3)6.5 Total impact

• Article: Ferromagnetic resonance and magnetoelastic demodulation in thin active films with an uniaxial anisotropy

  A. Klimov, Yu. Ignatov, N. Tiercelin, V. Preobrazhensky, P. Pernod, S. Nikitov
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  ABSTRACT: The results of experimental and theoretical studies of ferromagnetic resonance (FMR) and magnetoelastic excitations near the spin reorientation transition (SRT) in an uniaxial TbCo ₂/ FeCo layered nanostructure and a La _0.7 Sr _0.3 MnO ₃ film are reported. Experimental dependences of the amplitude of the reflected microwave signal versus the external magnetic field strength are presented in comparison with the theoretical ones. An increase in FMR reflectivity in the vicinity of SRT is clearly demonstrated. Low frequency magnetoelastic excitation of flexural vibrations of the samples by means of modulated microwave electromagnetic field is observed experimentally using a laser beam deflection technique. The increase in amplitude of vibrations at modulation frequency under combined FMR and SRT conditions is observed in agreement with the theory.
  Journal of Applied Physics 06/2010; · 2.17 Impact Factor
• Article: Investigations of surface and bulk spin wave modes in as-prepared and annealed FeNi multilayers by spin wave resonance

  R. Kordecki, R. Meckenstock, J. Pelzl, S. Nikitov
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  ABSTRACT: Magnetic multilayers consisting of alternating layers of polycrystalline Fe and Ni were investigated by spin wave resonance experiments at room temperature. Nonpropagating surface spin wave modes, as well as standing volume modes, could be observed in the perpendicular field configuration. The appearance of the surface modes is connected with the surface anisotropy at the bottom and the top layers of the structure. The experimental SWR spectra have been compared with the results of calculations. Values of the surface anisotropy, the effective spin wave stiffness constant, and the effective magnetization of the multilayered structure were deduced from the measured spectra for as-prepared and annealed samples. The results are compared with those obtained by torque measurements.
  Journal of Applied Physics 06/1993; · 2.17 Impact Factor
• Article: Ferromagnetic resonance investigations of spin waves in Fe‐Ni multilayers

  R. Kordecki, R. Meckenstock, J. Pelzl, H. Muhlbauer, G. Dumpich, S. Nikitov
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  ABSTRACT: The standing spin‐wave resonance (SSWR) at 9.2 GHz has been investigated in a multilayer structure composed of alternating layers of Ni and Fe for the as‐prepared sample and at different annealing temperatures between 420 and 570 K. Changes of the resonance field and of the intensity of spin‐wave modes with annealing temperature indicate the excitation of a surface mode in the as‐prepared sample. Heating of the multilayer above 520 K leads to a spin‐wave spectrum which exhibits a behavior corresponding to an alloy with comparable chemical composition. The SSWR fields show a quadratic dependence of the wave number of the spin waves at all annealing temperatures but a drastic change of surface spin pinning with increasing temperature.
  Journal of Applied Physics 12/1991; · 2.17 Impact Factor