Scattering
of spin waves by the interface of biaxial ferromagnets
V.
D. Poimanov
1,
V. V. Kruglyak 2,
V. G. Shavrov 3
1
Donetsk National
University, Universitetskaya 24, Donetsk 83001, Ukrain
2 University
of Exeter, Stocker Road, Exeter, EX4 4QL,
United Kingdom
3 Kotelnikov Institute of Radioengineering and
Electronics of Russian Academy of Sciences, Mokhovaya 11-7, Moscow 125009, Russia
The paper is received on November 19, 2018
Abstract.
The paper studies the scattering of exchange spin
waves at the interface of semi-infinite magnets with a uniform ground state.
The conditions for the formation of inhomogeneous exchange spin waves (GSSB)
corresponding to the imaginary roots of the characteristic equation are considered.
Such solutions arise in biaxial magnets, in which axial symmetry is absent,
which leads to the elliptical precession of magnetization. The effect is
considered for the case of small ellipticities of precession in the framework
of perturbation theory. The amplitude reflection and transmission coefficients
were obtained and their analysis was performed. It is shown that, depending on
the frequency ratio of homogeneous FMR in contacting ferromagnets, the
frequency dependence of the reflection coefficient can be monotonic or have a
minimum. The origin of the latter can be traced to the condition of equality of
the wave impedances in the limiting case of circular precession. At the same
time, the introduction of wave impedances into consideration in the case of
elliptical precession is not possible. The frequency dependence of the
transmission coefficient always remains monotonous.
Keywords:
biaxial ferromagnet, inhomogeneous spin waves, ellipticity, boundary conditions.
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For citation:
V. D. Poimanov, V. V. Kruglyak,
V. G. Shavrov. Scattering
of spin waves by the interface of biaxial ferromagnets.
Zhurnal Radioelektroniki - Journal of
Radio Electronics. 2018. No.
11. Available at
http://jre.cplire.ru/jre/nov18/17/text.pdf
DOI
10.30898/1684-1719.2018.11.17