Pavel A. Kolodin

Modeling of microwave magnetic envelope solitons in thin ferrite films through the nonlinear Schrödinger equation

A theoretical analysis of microwave magnetic envelope soliton profiles and the soliton peak power response for high power magnetostatic wave (MSW) excitations in yttrium iron garnet (YIG) thin films has been made. This analysis was based on the standard nonlinear Schrodinger equation with all key parameters based on experiment. The measurements were done for magnetostatic backward volume waves in a 10.2 μm YIG film, with a band edge at 5.06–5.07 GHz and operating point frequencies from 4.80 to 5.00 GHz. The use of accurate dispersion and group velocity parameters and the transmitted power versus frequency response of the MSW signal was critical. It was possible to accurately model both the shapes of the soliton pulses and the peak output versus peak input power response over a wide range of power levels.

Mode beating of spin wave beams in ferrimagnetic Lu/sub 2.04/Bi/sub 0.96/Fe/sub 5/O/sub 12/ films

We report on measurements of the two-dimensional intensity distribution of linear and non-linear spin wave excitations in a LuBiFeO film. The spin wave intensity was detected using a high-resolution Brillouin light scattering spectroscopy setup. The observed snake-like structure of the spin wave intensity distribution is understood as a mode beating between modes with different lateral spin wave amplitude distributions. The theoretical treatment of the linear regime is performed analytically, whereas the propagation of non-linear spin waves is simulated by a numerical solution of a non-linear Schrodinger equation with suitable boundary conditions.

Excitation of propagating dipole-exchange spin waves in ferromagnetic double-film structure

A theory of linear excitation of spin waves in perpendicularly magnetized double-film ferromagnetic film structures is developed. Dipole and exchange interaction as well as surface spin pinning conditions are taken into account. Expressions for spin-wave response functions and radiation resistance of a microstrip transducer for the double-film structure are derived. >

Propagation of linear and nonlinear spin wave excitations in YIG and Lu2.04Bi0.96Fe5O12 films studied by space resolved Brillouin light scattering (abstract)

We have investigated the propagation of surface and backward volume spin waves (BVSW) with the in-plane wavevector k∥=10–900 cm−1 excited by microwaves in YIG and Lu2.04Bi0.96Fe5O12 (LBIG) films with the film thicknesses 5 and 1.5 μm, respectively. In all cases the magnetization and k∥ were in the film plane. The frequencies of the spin wave excitations as well as the spatial distribution of their intensities in the linear and in the nonlinear excitation regime were measured by means of a fully automated, high-stabilization, small-angle Brillouin light scattering (BLS) setup with a spatial resolution of 30 μm. It is well known1 that in the case of BVSW modes, the Lighthill criterion2 for modulational instability is fulfilled for both the longitudinal and the transverse perturbations of the initially constant-amplitude wave beam. Therefore, this mode is very much suitable for the investigation of the evolution of a plane-front, constant-amplitude initial beam, and for a direct experimental study of two-dim...

Ferromagnetic Film Convolver Based on Resonance Confluence of Backward Spin Waves

The results of theoretical and experimental investigations of three magnon confluence of two backward volume waves in a surface one in a tangentially magnetized ferromagnetic film-are presented. These investigations have shown that this process is very effective one, so it can be used to design a new type of convolver.

Frequency and phase selective magnetostatic wave switch

A new type of magnetostatic wave gate microwave switch, which has both frequency and phase selectivity features, is presented. This switch is triggered by microwave signal and has output amplitude modulation over 30 dB and phase sensitivity about 1 dB/grad. Only the signals which match the gate frequency and phase are passed by the switch, therefore it fulfils not only switching features but features of a phase and frequency matched filter as well.

On the Frequency Characteristics of Spin-Wave Convolver

This paper presents the results of the first investigations of the frequency characteristics of the new type of spin-wave convolver based on the resonance confluence of the backward volume spin waves. The oscillation of the output signal frequency dependence have been observed. The frequency dependence of the bilinearity coefficient have been investigated. The very hight value of the bilinearity coefficient (¿35 dBm) have been obtained. Theoretical explanation of the experimental data are given.

Amplification of Microwave Magnetic Envelope Solitons in Yttrium Iron Garnet Thin Films by Parallel Pumping

The parametric amplification of 4.01 GHz, 22 ns wide microwave magnetic envelope (MME)backward volume wave pulses by parallel pumping has been realized in yttrium iron garnet (YIG)films. The parametric parallel pumping was achieved with 15–23 ns wide pulses applied to a strip lineresonator at a frequency v

Spin-wave Resonance Convolver With Broad Freouency Band

Spin-wave convolution process based on the resonance confluence of two backward volume spin waves with the frequencies 01, 0 2 and wave vectors K1, K2 into propagating surface spin wave with 0 3 , Kg offers an advantage of very high convolution efficiency [1,2] in comparison with other types of spin-wave convolvers (see for example [3] and references therein). One of the disadvantages of the resonance convolver is the comparatively low operating frequencies. This restriction follows from the conservation laws for three magnon processes: