Phase-transition kinetics of magnetic skyrmions investigated by stroboscopic small-angle neutron scattering

Authors

Taro Nakajima, Yasuhiro Inamura, Takayoshi Ito, Kazuki Ohishi, Hiroshi Oike, Fumitaka Kagawa, Akiko Kikkawa, Yasujiro Taguchi, Kazuhisa Kakurai, Yoshinori Tokura, and Takahisa Arima

Abstract

We investigated the phase-transition kinetics of magnetic skyrmion lattice (SkL) in MnSi by means of stroboscopic small-angle neutron scattering (SANS). Temporal evolutions of SANS patterns were measured with time resolution of 13 ms while sweeping temperature as fast as $50{\mathrm{Ks}}^{-1}$. It turned out that the paramagnetic-to-SkL transition immediately occurs upon traversing the equilibrium phase boundary on the rapid cooling, whereas the SkL-to-conical transition can be kinetically avoided to realize the low-temperature metastable SkL with a long-range magnetic order. The formation of the metastable SkL was found to be strongly dependent not only on cooling rate, but also on magnetic field and trajectory in the $H\text{−}T$ phase diagram.

Physical Review B : https://journals.aps.org/prb/abstract/10.1103/PhysRevB.98.014424