Synthesizing skyrmion bound pairs in Fe-Gd thin films

Abstract

We show that properly engineered amorphous Fe-Gd alloy thin films with perpendicular magnetic anisotropy (PMA) exhibit bound pairs of like-polarity, opposite helicity skyrmions at room temperature. Magnetic mirror symmetry planes present in the stripe phase, instead of chiral exchange, determine the internal skyrmion structure and the net achirality of the skyrmion phase. Our study shows that stripe domain engineering in amorphous alloy thin films may enable the creation of skyrmion phases with technologically desirable properties.

Nanosecond X-Ray Photon Correlation Spectroscopy on Magnetic Skyrmions

“…They were deposited on 50 nm Si 3 N 4 membranes and were measured in a forward scattering geometry. The samples were precharacterized at the coherent soft x-ray beam line (12.0.2.2) of the Advanced Light Source (ALS) [39] using a prescripted magnetic field cycle [40]. The sample was shown to exhibit an aligned stripe domain state and a Skyrmion state at room temperature between perpendicular magnetic fields of μ 0 H ≈ 0À150 and μ 0 H ≈ 150À250 mT, respectively (see Fig.…”

“…The small ROI was used in order to acquire data at the repetition rate of the LCLS (120 Hz). An electromagnet was used to apply an out-of-plane magnetic field, with a tilt of 3.5°in order to reproduce a small, in-plane field [40]. A microchannel plate (MCP) placed between the monochromator and the sample was used for monitoring the energies of each x-ray pulse individually.…”

Experimental and Modeling Study of Ferrimagnetic Rare-Earth Transition-Metal Thin Films

“…Finally, other spintronic techniques have been proposed such as racetrack memory 15 and Skyrmion meory [16][17][18] for applications of even lower power consumption. For example, as topologicalprotected solitons, Skyrmions were proved to be stable in two dimensional surfaces.…”

“…the GdFe thin films. 18 This discovery opens opportunities to explore new physics as well as ultralow-power spintronic devices.…”

“…12,14 Moreover, Skyrmion state has recently been reported in GdFe. 18 These findings make RE-TM thin films promising for future high-speed, low-current spintronic devices. This chapter will present a modeling study of ultrafast dynamics of the RE-TM thin film.…”