Phys.org February 5, 2021
The magnitude of the conventional inductance is proportional to the volume of the inductor’s coil, which hinders the miniaturization of inductors. Researchers in Japan have demonstrated an inductance of quantum-mechanical origin, generated by the emergent electric field induced by current-driven dynamics of spin helices in a magnet. In microscale rectangular magnetic devices with nanoscale spin helices, they observed a typical inductance as large as −400 nanohenry, comparable in magnitude to that of a commercial inductor, but in volume about a million times smaller. The inductance is enhanced by nonlinearity in current and shows non-monotonous frequency dependence, both of which result from the current-driven dynamics of the spin-helix structures. The magnitude of the inductance rapidly increases with decreasing device cross-section, in contrast to conventional inductors. The findings may pave the way to microscale, simple-shaped inductors based on emergent electromagnetism related to the quantum-mechanical Berry phase…read more. TECHNICAL ARTICLE
Concept of emergent inductance. Credit: Nature volume 586, pages232–236(2020)