Aki Kitaori

Emergent electromagnetic induction based on electrodynamics of noncollinear spin states may enable dramatic miniaturization of inductor elements widely used in electric circuits, yet the research is still in its infancy and many issues must be resolved toward its application. One such problem is how to increase working temperature to room temperature, and possible thermal agitation effects on the quantum process of the emergent induction are unknown. We report here large emergent electromagnetic

Ac current-driven motions of spiral spin textures can give rise to emergent electric fields acting on conduction electrons. This in turn leads to the emergent electromagnetic induction effect which may realize quantum inductor elements of micrometer size. ${\mathrm{YMn}}_{6}{\mathrm{Sn}}_{6}$ is a helimagnet with a short helical period (2--3 nm) that shows this type of emergent inductance beyond room temperature. To identify the optimized materials conditions for ${\mathrm{YMn}}_{6}{\mathrm{Sn}}

In helimagnetic metals, ac current-driven spin motions can generate emergent electric fields acting on conduction electrons, leading to emergent electromagnetic induction (EEMI). Recent experiments reveal the EEMI signal generally shows a strongly current-nonlinear response. In this study, we investigate the EEMI of Tb₅Sb₃, a short-period helimagnet. Using small angle neutron scattering we show that Tb₅Sb₃ hosts highly disordered helimagnetism with a d

Nonreciprocal resistance, depending on both directions of current $\mathbit{j}$ and magnetic-field $\mathbit{H}$ or magnetization $\mathbit{M}$, is generally expected to emerge in a chiral conductor and be maximized for $\mathbit{j}\phantom{\rule{4pt}{0ex}}\ensuremath{\parallel}\phantom{\rule{4pt}{0ex}}\mathbit{H}(\mathbit{M}$). This phenomenon, electrical magnetochiral effect (eMChE), is empirically known to increase with $H$ in a paramagnetic or fully ferromagnetic state on chiral lattice or t

We have successfully grown single crystalline Tb5Sb3 with the hexagonal structure, which was reported to exhibit successive transitions among complex spiral magnetic structures with changing temperature. Through the measurements of specific heat and magnetization of the single crystalline Tb5Sb3, we have identified only one clear magnetic transition at 133 K. The ordered moments are approximately oriented in the hexagonal basal plane, while the hard axis of magnetization corresponds to the [0001