Magnetic properties of quenched binary and ternary quasicrystal approximants.

The magnetic properties of binary Gd-Cd and ternary Gd-Au-Ge crystals obtained from the newly introduced low-melt peritectic formation (LMPF) synthesis method were investigated. This method consists of a rapid quenching of the metallic melt followed by an annealing treatment at a relevant temperature. In the first system, both quasicrystal (QC) and approximant crystal (AC) phases can be stabilized, whereas only the AC phase is obtainable in the pseudo-binary Gd-(Au-Ge) system.

Superconducting YAuSi and Antiferromagnetic GdAuSi with an Interpenetrating Framework Structure Built from 16-Atom Polyhedra.

Investigations of reaction mixtures RE(AuSi) (RE = Y and Gd) yielded the compounds REAuSi which adopt a new structure type, referred to as GdAuSi structure (80, 4/, = 16, = 12.8244(6)/12.7702(2) Å, and = 9.

Atomic-Scale Tuning of Tsai-Type Clusters in RE-Au-Si Systems (RE = Gd, Tb, Ho).

Tsai-type quasicrystals and approximants are distinguished by a cluster unit made up of four concentric polyhedral shells that surround a tetrahedron at the center. Here we show that for Tsai-type 1/1 approximants in the RE-Au-Si systems (RE = Gd, Tb, Ho) the central tetrahedron of the Tsai clusters can be systematically replaced by a single RE atom. The modified cluster is herein termed a "pseudo-Tsai cluster" and represents, in contrast to the conventional Tsai cluster, a structural motif without internal symmetry breaking.

Inertia-driven resonant excitation of a magnetic skyrmion.

Topological spin structures such as magnetic domain walls, vortices, and skyrmions, have been receiving great interest because of their high potential application in various spintronic devices. To utilize them in the future spintronic devices, it is first necessary to understand the dynamics of the topological spin structures. Since inertial effect plays a crucial role in the dynamics of a particle, understanding the inertial effect of topological spin structures is an important task.

Antiferromagnetic Domain Wall Motion Driven by Spin-Orbit Torques.

We theoretically investigate the dynamics of antiferromagnetic domain walls driven by spin-orbit torques in antiferromagnet-heavy-metal bilayers. We show that spin-orbit torques drive antiferromagnetic domain walls much faster than ferromagnetic domain walls. As the domain wall velocity approaches the maximum spin-wave group velocity, the domain wall undergoes Lorentz contraction and emits spin waves in the terahertz frequency range.