Self-Intercalation as Origin of High-Temperature Ferromagnetism in Epitaxially Grown Fe_{5}GeTe_{2} Thin Films.

The role of self-intercalation in 2D van der Waals materials is key to the understanding of many of their properties. Here we show that the magnetic ordering temperature of thin films of the 2D ferromagnet Fe_{5}GeTe_{2} is substantially increased by self-intercalated Fe that resides in the van der Waals gaps. The epitaxial films were prepared by molecular beam epitaxy and their magnetic properties explored by element-specific x-ray magnetic circular dichroism that showed ferromagnetic ordering up to 375 K.

Current-induced domain wall motion in a van der Waals ferromagnet FeGeTe.

The manipulation of spin textures by spin currents is of fundamental and technological interest. A particularly interesting system is the 2D van der Waals ferromagnet FeGeTe in which Néel-type skyrmions have recently been observed. The origin of these chiral spin textures is of considerable interest.

Thickness-Tunable Zoology of Magnetic Spin Textures Observed in FeGeTe.

The family of two-dimensional (2D) van der Waals (vdW) materials provides a playground for tuning structural and magnetic interactions to create a wide variety of spin textures. Of particular interest is the ferromagnetic compound FeGeTe that we show displays a range of complex spin textures as well as complex crystal structures. Here, using a high-brailliance laboratory X-ray source, we show that the majority (1 × 1) FeGeTe (FGT5) phase exhibits a structure that was previously considered as being centrosymmetric but rather lacks inversion symmetry.

Generation of out-of-plane polarized spin current by spin swapping.

The generation of spin currents and their application to the manipulation of magnetic states is fundamental to spintronics. Of particular interest are chiral antiferromagnets that exhibit properties typical of ferromagnetic materials even though they have negligible magnetization. Here, we report the generation of a robust spin current with both in-plane and out-of-plane spin polarization in epitaxial thin films of the chiral antiferromagnet MnSn in proximity to permalloy thin layers.

Li iontronics in single-crystalline T-NbO thin films with vertical ionic transport channels.

The niobium oxide polymorph T-NbO has been extensively investigated in its bulk form especially for applications in fast-charging batteries and electrochemical (pseudo)capacitors. Its crystal structure, which has two-dimensional (2D) layers with very low steric hindrance, allows for fast Li-ion migration. However, since its discovery in 1941, the growth of single-crystalline thin films and its electronic applications have not yet been realized, probably due to its large orthorhombic unit cell along with the existence of many polymorphs.