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arXiv · 1411.2452

Magnon spectrum in ferromagnets with a skyrmion

D. N. Aristov·S. S. Kravchenko·A. O. Sorokin
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Abstract

The analysis of the spin wave excitations in two-dimensional isotropic Heisenberg ferromagnet is performed with a single skyrmion in the ground state. We employ the ideas of semiclassical quantization method, duly modified for the use of the lattice model and Maleyev-Dyson boson representation of spin operators. The resulting Schr\"odinger equation for magnons describes the dispersion and wave functions of spin-wave excitations with strictly non-negative spectrum. In contrast to usual ferromagnet, we demonstrate the existence of three zero modes, corresponding to conformal symmetries spontaneously violated by the skyrmion configuration.

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D. N. Aristov, S. S. Kravchenko, A. O. Sorokin. 2014-11-10. Magnon spectrum in ferromagnets with a skyrmion. https://doi.org/10.1134/s0021364015190029

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