The dynamics of domain wall Skyrmions

Abstract

It has recently been shown that Skyrmions with a fixed size can exist in theories without a Skyrme term, providing the Skyrmion is located on a domain wall. Here we numerically compute domain wall Skyrmions of this type, in a (2+1)-dimensional O(3) sigma model with a potential term. Moreover, we investigate Skyrmion dynamics, to study both Skyrmion stability and the scattering of multi-Skyrmions. We demonstrate that scattering events in which both Skyrmions remain on the same domain wall are effectively one-dimensional, and at low speeds are well-approximated by kink scattering in the integrable sine-Gordon model. However, more exotic fully two-dimensional scatterings are also presented, in which Skyrmions that are initially on different domain walls emerge on the same domain wall.

Incarnations of Skyrmions

“…A similar relation is known in d ¼ 2 þ 1 dimensions, in which lumps [13] or baby Skyrmions [14,15] become sine-Gordon kinks [16][17][18] when trapped inside a CP 1 domain wall [19,20], corresponding to entry (a) in Table I. This relation was already known earlier in condensed matter systems such as Josephson junctions of two superconductors [21], ferromagnets [22], and 3 He superfluids [3].…”

Magnetothermodynamics of BPS baby skyrmions

“…To overcome the computational difficulties and learn something about the electromagnetic properties of BPS Skyrme type solitons, one can analyze lower-dimensional analogs, as has been done successfully already in many occasions. In fact, there exists a (2 + 1) dimensional version of the Skyrme model, usually referred to as the baby Skyrme model, which supports solitonic solutions (baby skyrmions) [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38] (for the gauged version see [39,40]). This field theory also possesses its BPS limit, whose Lagrangian consists of the (2+1) dimensional version of the Skyrme term and a potential [41][42][43].…”

Microscopic description of twisted magnet Cu2OSeO3

“…Secondly, being an insulator, Cu 2 OSeO 3 has magnetic-electric properties [14][15][16][17][18][19][20], which provide a new physical significance in comparison with the B20 crystals. The interconnection between magnetization gradients and electric polarization makes this crystal potentially applicable for data storing devices and spintronics [21][22][23][24]. And thirdly, but not finally, being more complex than the B20 structures (16 magnetic copper atoms in two non-equivalent positions in the unit cell) makes it an interesting object for studying spin textures.…”