A new type of ferromagnetism that can be turned on and off electrically has been found on the interface of two non-magnetic oxide materials. The results have been accepted by Nature Communication, and will open a gateway to new types of spintronic and quantum devices.
Previous PQI graduate student Feng has found that on the interface of LaAlO3/SrTiO3, when LaAlO3 is 12 unit cells thick, will demonstrate tunable ferromagnetism by external electric field in room temperature. The interface was known to be highly conductive with the presence of 2D electron gas. Feng found that when the 2D electron gas was driven away by electric field, ferromagnetism would appear on the interface. The magnetism was measured with a highly sensitive atomic force microscope with a magnetized tip, and magnetic dipoles appeared to be in the same plane as the oxide interface.
- Bi, F. et al. "Room-Temperature Electronically-Controlled Ferromagnetism at the LaAlO3/SrTiO3 Interface," Nature Communication 5, 5019 (2014).