Contact solitons as spin pistons in one-dimensional ferromagnetic channels

Contact solitons are nonlinear solutions in one-dimensional ferromagnetic channels subject to spin injection in one edge [1]. Similar solutions have also been shown to exist by micromagnetic simulations where the injection is located within the channel [2]. Effectively, these are solitons that give rise to a large-amplitude in-plane state known as a dissipative exchange flow DED or spin superfluid [3]. Here, we show that the contact soliton can be modulated, leading to a modulation of the ensuing DEF [4]. With this method, we show that the modulation is a spin wave which follows the expected Bogoliubov – de Gennes dispersion relation. At low frequencies, this dispersion is effectively linear. The extension of this work into two interacting contact solitons will also be outlined.

References:

[1] E. Iacocca and M. A. Hoefer, Phys. Rev. B 99, 184402 (2019)

[2] T. Schneider et al., Phys. Rev. B 103, 144412 (2021)

[3] E. Iacocca and M. A. Hoefer, Phys. Lett. A 383, 125858 (2019)

[4] M. Estiphanos and E. Iacocca, arXiv:2407.02628