Nonconventional magnetic phenomena in neodymium thin film

Fundamental difference in the electronic reconstruction of infinite-layer vs. perovskite neodymium nickelate films on SrTiO$_3$(001)

Motivated by recent reports of superconductivity in Sr-doped NdNiO$_2$ films on SrTiO$_3$(001) [Nature (London) 572, 624 (2019)], we explore the role of the polar interface on the structural and electronic properties of NdNiO$_n$/SrTiO$_3$(001) ($n=2,3$) by performing first-principles calculations including a Coulomb repulsion term. For infinite-layer nickelate films ($n=2$), electronic reconstruction drives the surprising emergence of a two-dimensional electron gas (2DEG) at the interface involving a strong occupation of the Ti $3d$ states. This effect is more pronounced than in LaAlO$_3$/SrT…

带覆盖层与不带覆盖层的无限层钕镍酸盐薄膜中的电荷分布

Charge distribution across capped and uncapped infinite-layer neodymium nickelate thin films

本研究结合STEM-EELS、HAXPES与4D-STEM，比较带覆盖层和无覆盖层NdNiO₂薄膜，揭示顶氧重嵌入诱导的条纹、空穴掺杂及其与电荷有序的可能联系。

Self-induced spin glass state in elemental and crystalline neodymium

Spin glasses are a highly complex magnetic state of matter, intricately linked to spin frustration and structural disorder. They exhibit no long-range order and exude aging phenomena, distinguishing them from quantum spin liquids. We report a new type of spin glass state, the spin-Q glass, observable in bulk-like crystalline metallic neodymium thick films. Using spin-polarized scanning tunneling microscopy combined with ab initio calculations and atomistic spin-dynamics simulations, we visualize the variations in atomic-scale non-collinear order and its response to magnetic field and temperatu…

Strain Engineering of Magnetic Anisotropy in Epitaxial Films of Cobalt Ferrite

Perpendicular magnetic anisotropy (PMA) energy up to $K_{\mathrm{u}}=6.1\pm0.8$ MJ m$^{-3}$ is demonstrated in this study by inducing large lattice-distortion exceeding 3% at room temperature in epitaxially distorted cobalt ferrite Co$ _{x} $Fe$ _{3-x} $O$ _{4} $ (x = 0.72) (001) thin films. Although the thin film materials include no rare-earth elements or noble metals, the observed $ K_{u} $ is larger than that of the neodymium-iron-boron compounds for high-performance permanent magnets. The large PMA is attributed to the significantly enhanced magneto-elastic effects, which are pronounced i…

厚度依赖的稀土元素在磁ron溅射沉积的NdCo$_{4.6}$薄膜中的富集研究：通过X射线反射率和硬X射线光电子能谱

Thickness dependent rare earth segregation in magnetron deposited NdCo$_{4.6}$ thin films studied by Xray reflectivity and Hard Xray photoemission

研究通过X射线反射率和HAXPES揭示NdCo$_{4.6}$薄膜中Nd的厚度依赖性富集，揭示了Nd在钴晶格中的各向异性环境形成机制。

A nano-carbon route to rare earth free permanent magnetism

High coercivity magnets are an important resource for renewable energy, electric vehicles and memory technologies. Most hard magnetic materials incorporate rare-earths such as neodymium and samarium, but the concerns about the environmental impact and supply stability of these materials is prompting research into alternatives. Here, we present a hybrid bilayer of cobalt and the nano-carbon molecule C60 which exhibits significantly enhanced coercivity with minimal reduction in magnetisation. We demonstrate how this anisotropy enhancing effect cannot be described by existing models of molecule-m…