We have studied experimentally the linear and nonlinear control over the phase accumulation in a spin-wave phase shifter, which is a key element for construction of spin-wave logic devices. The linear control is realized by creation of a local inhomogeneity of the bias magnetic field, whereas the nonlinear control is based on the shift in the spin-wave dispersion spectrum with the increase in the spin-wave amplitude. We show that in a single device these two mechanisms can have comparable efficiencies and relatively small cross talk, which allows their simultaneous use for realization of dual-argument logic operations.

We have studied the tunneling of spin-wave pulses through a system of two closely situated potential barriers. The barriers represent two areas of inhomogeneity of the static magnetic field, where the existence of spin waves is forbidden. We show that for certain values of the spin-wave frequency corresponding to the quantized spin-wave states existing in the well formed between the barriers, the tunneling has a resonant character. As a result, transmission of spin-wave packets through the double-barrier structure is much more efficient than the sequent tunneling through two single barriers.

Using low-loss dielectric magnetic films in combination with space-resolved Brillouin light scattering spectroscopy we have studied nonlinear modification of eigenmode spatial distributions in saturated magnetic squares. We have found that, as the angle of magnetization precession increases, the eigenmode spatial distributions experience significant qualitative changes due to a nonlinear coupling between forming them standing spin waves. We show that the found nonlinear eigenmodes cannot be described by means of the linear theoretical approach even qualitatively.

Modifications of spatial distributions of dynamic magnetization corresponding to spinwave eigenmodes of magnetic squares subjected to a strong microwave excitation field have been studied experimentally and theoretically. We show that an increase of the excitation power leads to a nonlinear generation of long-wavelength spatial harmonics caused by the nonlinear cross coupling between the eigenmodes. The analysis of the experimental data shows that this process is mainly governed by the action of the nonlinear spin-wave damping. This conclusion is further supported by the numerical calculations based on the complex Ginzburg-Landau equation phenomenologically taking into account the nonlinear damping.Comment: 23 pages, 6 figure

Formation of stationary longitudinal amplitude patterns by propagating nonlinear spin waves has been discovered and studied experimentally by means of space-resolved Brillouin light scattering spectroscopy. The pattern formation is observed for spin waves propagating in narrow, longitudinally magnetized yttrium iron garnet stripes, characterized by attractive nonlinearity in both the longitudinal and transverse directions. A clear crossover of the effective dimensionality describing the propagation of spin waves in the stripe is observed with increase of the wave amplitude.