Theory of Linear Spin Wave Emission from a Bloch Domain Wall

We report an analytical theory of linear emission of exchange spin waves from a Bloch domain wall, excited by a uniform microwave magnetic field. The problem is reduced to a one-dimensional Schr\"odinger-like equation with a P\"oschl-Teller potential and a driving term of the same profile. The emission of plane spin waves is observed at excitation frequencies above a threshold value, as a result of a linear process. The height-to-width aspect ratio of the P\"oschl-Teller profile for a domain wall is found to correspond to a local maximum of the emission efficiency. Furthermore, for a tailored P\"oschl-Teller potential with a variable aspect ratio, particular values of the latter can lead to enhanced or even completely suppressed emission.Comment: added ancillary file

Spin waves in a magnonic crystal with sine-like interfaces

Abstract The spectrum of exchange spin waves in a magnonic crystal (periodic magnetic multilayer) with diffuse interfaces is derived for a model with a cosine-like profile of the uniaxial anisotropy value at the interfaces. The dependence of the band gap size upon the interface thickness and the depth of modulation of the anisotropy value is analyzed. In particular, it is shown that diffuse interfaces may lead to a magnonic spectrum in which band gaps have size equal to or even larger than those in the model with sharp (infinitely thin) interfaces (Kronnig-Penney model). r 2006 Elsevier B.V. All rights reserved. Keywords: Magnonics; Magnon; Superlattice; Nanomagnetism Due to the wealth results of investigations of photonic crystals [1] and other similar objects with artificially created periodicity [2-6], periodic magnetic structures have received a renewed attention. Such structures could be used to control the propagation of spin waves (SW) While most of the theoretical efforts have been devoted to investigation of MCs with infinitely thin interfaces Gorobets et al