Special Physics Seminar

Superfluid Spin Transport in Quantum Materials

Se Kwon Kim

UCLA

Recent advancements in spintronic techniques originally developed for spin-based devices now enable us to study fundamental spin physics of quantum materials with unprecedented spin-current control and measurement, opening a new area of theoretical and experimental investigation. One phenomenon emerging in the aforementioned direction is superfluid spin transport in magnetic insulators, a magnetic analog of mass superfluidity, which has been envisioned about a half century ago and can now be realized with the aid of spin-current sources and detectors developed in spintronics. When the medium for superfluid spin transport is a quantum spin chain, topological quantum effects influence spin transport significantly, differentiating the decaying rate of the spin supercurrent between the integer versus half-odd-integer spin chains. The spin-parity dependence of the decaying rate can be probed in a magnetoelectric circuit. Analogous investigations of spin transport are envisioned in quantum materials such as strontium ruthenate and cuprates.