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arXiv · 2103.16205

Critical Sample Aspect Ratio and Magnetic Field Dependence for Antiskyrmion Formation in Mn1.4PtSn Single-Crystals

Abstract

Mn1.4PtSn is the first material in which antiskyrmions have been observed in ultra-thin single crystalline specimens. While bulk crystals exhibit fractal patterns of purely ferromagnetic domain ordering at room temperature, ultra-thin Mn1.4PtSn lamellae clearly show antiskyrmion lattices with lattice spacings up to several $\mu$m. In the work presented here, we systematically investigate the thickness region from 400 nm to 10 $\mu$m using 100 $\times$ 100 $\mu$m$^2$ -wide Mn1.4PtSn plates, and identify the critical thickness-to-width aspect ratio $\alpha_0 = 0.044$ for the ferromagnetic fractal domain to the non-collinear texture phase transition. Additionally, we also explore these non-collinear magnetic textures below the critical aspect ratio $\alpha_0$ above and below the spin-reorientation transition temperature $T_{SR}$ while applying variable external magnetic fields. What we find is a strong hysteresis for the occurrence of an antiskyrmion lattice, since the antiskyrmions preferentially nucleate by pinching them off from helical stripes in the transition to the field polarized state.

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Belen E. Zuniga Cespedes, P. Vir, Peter Milde, C. Felser, L. Eng. 2021-03-30. Critical Sample Aspect Ratio and Magnetic Field Dependence for Antiskyrmion Formation in Mn1.4PtSn Single-Crystals. https://doi.org/10.1103/physrevb.103.184411

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