The University of Tokyo · 물리·천문학
Aki Kitaori 교수의 연구실은 헬리마그네틱 재료에서 기인하는 양자적 스핀 구조가 유도하는 잠재적 전자기 유도 현상, 특히 '비국소적 전자기 유도(Emergent Electromagnetic Induction, EEMI)'를 중심으로 연구를 전개하고 있습니다. 주로 허브-스피넬 구조를 가진 희토류 금속 산화물 및 희토류-锑 화합물에서 발생하는 짧은 주기의 스핀 스피RAL 상태를 활용해, 실온에서 작동하는 마이크로미터 크기의 양자 인덕터 소자 실현 가능성을 탐색하고 있습니다. 특히 스핀의 비정상적 동역학과 전기적 비선형성, 비상향성 전기 저항 현상 등에 대한 실험적 분석을 통해 새로운 전자소자 원리를 규명하고자 합니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
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 Tb<sub>5</sub>Sb<sub>3</sub>, a short-period helimagnet. Using small angle neutron scattering we show that Tb<sub>5</sub>Sb<sub>3</sub> 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
