One-dimensional dynamics of magnetic inhomogeneities in a three-layer ferromagnetic structure with different values of the magnetic parameters

E.G. Ekomasov, R.V. Kudryavtsev, A.M. Gumerov show affiliations and emails
Received 15 April 2017; Accepted 11 May 2017;
This paper is written in Russian
Citation: E.G. Ekomasov, R.V. Kudryavtsev, A.M. Gumerov. One-dimensional dynamics of magnetic inhomogeneities in a three-layer ferromagnetic structure with different values of the magnetic parameters. Lett. Mater., 2017, 7(2) 160-164


In this paper, we considered a three-layer ferromagnetic structure, which consists of two broad layers separated by a thin layer. The parameters of magnetic anisotropy, exchange and damping are considered functions of the coordinate directed perpendicular to the interface of the layers. The case of a point magnetic defect described with the help of the Dirac delta-function is studied with the values of the parameters of magnetic anisotropy, exchange and damping, which differ from the values of the analogous parameters in the remaining magnet. The dynamics of the domain wall is studied theoretically with allowance for the excitation of localized magnetization waves in the region of the magnetic defect. Using the collective-coordinate approach, a system of two equations is obtained for the coordinate of the DW center and the amplitude of the oscillations of the magnetization wave localized in the defect region. From the analysis of this system of equations, it is found how the inhomogeneity of the damping and exchange parameter affects the dynamics of magnetic inhomogeneities. The value of the effective dissipation coefficient is determined, which for the case of motion of the domain wall now becomes dependent on the position of the domain wall. It is shown that accounting for heterogeneity of dissipation and exchange can significantly change the speed and scenario of the dynamics of the DW. The dependence of the minimum value of the magnetic field on the dissipation and exchange inhomogeneity coefficients, at which the DW passes through the defect region, is found.

References (14)

1. Denny D. Tang, Yuan-Jen Le. Magnetic Memory Fundamentals and Technolog. Cambridge, Cambridge University Press, New York. (2010) 196 p.
2. A. B. Borisov, V. V. Kiselev. Quasi-one-dimensional magnetic solitons. Moscow, FIZMATLIT. (2014) 520 p. (in Russian) [А. Б. Борисов, В. В. Киселёв. Квазиодномерные магнитные солитоны. Москва, ФИЗМАТЛИТ. 2014. 520 с.].
3. E. Della Torre, C. M. Perlov. J. Appl. Phys. 69, 4596 (1991).
4. V. N. Nazarov, R. R. Shafeev, M. A. Shamsutdinov, I. Yu Lomakina. Phys. Solid State. 54, 298 (2012). (in Russian) [В. Н. Назаров, Р. Р. Шафеев, М. А. Шамсутдинов, И. Ю. Ломакина. ФТТ. 54 (2), 282 (2012).].
5. V. V. Kiselev, A. A. Rascovalov. Chaos, Solitons & Fractals. 45, 1551 (2012).
6. V. V. Kruglyak, A. N. Kuchko, V. I. Finokhin. Phys. Solid State. 46, 867 (2004). (in Russian) [В. В. Кругляк, А. Н. Кучко, В. И. Финохин. ФТТ. 46 (5), 842 (2004).].
7. E. G. Ekomasov, A. M. Gumerov, R. R. Murtazin, R. V. Kudryavtsev, A. E. Ekomasov, N. N. Abakumova. Solid state phenomena. 233 - 234, 51 - 54 (2015).
8. E. G. Ekomasov, R. R. Murtazin, V. N. Nazarov. Journal of Magnetism and Magnetic Materials. 385, 217 (2015).
9. V. A. Ignatchenko, Yu. I. Mankov, A. A. Maradudin. Phys. Rev. B. 62 (3), 2181 (2000).
10. J. Cuevas-Maraver, P. G. Kevrekidis, F. Williams (Eds.). The Sine-Gordon Model and Its Applications: From Pendula and Josephson Junctions to Gravity and High-energy Physics, volume 10. Springer. (2014) 263 p.
11. E. G. Ekomasov, R. R. Murtazin, O. B. Bogomazova, A. M. Gumerov. JMMM. 339, 133 (2013).
12. E. G. Ekomasov, A. M. Gumerov. Letters on materials. 4 (4), 237 - 240 (2014). (in Russian) [А. М. Гумеров, Е. Г. Екомасов. Письма о материалах. 3 (2), 103 - 105 (2013).].
13. E. G. Ekomasov, A. M. Gumerov, R. V. Kudryavtsev. Letters on materials. 6 (2), 138 - 140 (2016). (in Russian) [Е. Г. Екомасов, А. М. Гумеров, Р. В. Кудрявцев. Письма о материалах. 6 (2), 138 - 140 (2016).].
14. M. A. Shamsutdinov, V. N. Nazarov, I. Yu. Lomakina, and others. Ferro- and antiferromagnetodynamics. Nonlinear oscillations, waves and solitons. Moscow, Science. (2009) 368 p. (in Russian) [М. А. Шамсутдинов, В. Н. Назаров, И. Ю. Ломакина и др. Ферро- и антиферромагнитодинамика. Нелинейные колебания, волны и солитоны. Москва, Наука. 2009. 368 с.].

Similar papers