- Name of university
- Tohoku University
- Frontier Research Institute for Interdisciplinary Sciences
- Assistant Professor
- Device and Technology
Condensed Matter Theory, Magnetism
Condensed matter theory
Theoretical study on quantum relativistic inductance
In 1831, an English scientist Michael Faraday saw electric currents when he slid a bar magnet in and out of a coil of wires. This law of electromagnetic induction serves as a bedrock of modern civilization, offering the fundamental operating principle of many types of electrical generators, motors, and inductor devices. Physically, this phenomenon can be understood as the kinetic energy of the moving magnet has been converted to an electromotive force, via the law of classical electromagnetism.
In 2009, a new kind of electromotive force was experimentally reported. Now you don’t need to move a magnet. What is dynamical here is the magnetic nanostructure inside the magnet, which triggers a conversion of the internal energy of the magnet to an electromotive force. Today this effect is called spin-motive force (SMF). Interestingly, SMF turns out to have a deep connection with Faraday’s electromagnetic induction; from a modern quantum mechanical point of view, both phenomena can be attributed to the time-varying Berry phase of an electron wave function.
While SMF is still very young, it is as a basic and universal physical effect as the celebrated electromagnetic induction. SMF may provide a key element for next generation technologies. Now I am exploring the possibility of novel mechanism of electromagnetic inductance, combining SMF and the quantum relativistic spin-orbit coupling effects.