Stability of Néel-type skyrmion lattice against oblique magnetic fields in GaV${}_4$S${}_8$ and GaV${}_4$Se${}_8$

Abstract

The orientation of Néel-type skyrmions in the lacunar spinels GaV${}_4$S${}_8$ and GaV${}_4$Se${}_8$ is tied to the polar axes of their underlying crystal structure through the Dzyaloshinskii-Moriya interaction. In these crystals, the skyrmion lattice phase exists for externally applied magnetic fields parallel to these axes and withstands oblique magnetic fields up to some critical angle. Here, we map out the stability of the skyrmion lattice phase in both crystals as a function of field angle and magnitude using dynamic cantilever magnetometry. The measured phase diagrams reproduce the major features predicted by a recent theoretical model, including a reentrant cycloidal phase in GaV${}_4$Se${}_8$. Nonetheless, we observe a greater robustness of the skyrmion phase to oblique fields, suggesting possible refinements to the model. Besides identifying transitions between the cycloidal, skyrmion lattice, and ferromagnetic states in the bulk, we measure additional anomalies in GaV${}_4$Se${}_8$ and assign them to magnetic states confined to polar structural domain walls.

11 pages and 7 figures

References in corpus (4)

• A new class of chiral materials hosting magnetic skyrmions beyond room temperature
• Resistive switching induced by electronic avalanche breakdown in GaTa${}_4$Se${}_{8-x}$Te${}_x$ narrow gap Mott Insulators
• Skyrmion robustness in non-centrosymmetric magnets with axial symmetry: The role of anisotropy and tilted magnetic fields
• Characteristics of ferroelectric-ferroelastic domains in N{é}el-type skyrmion host GaV${}_4$S${}_8$