Insulating Magnets Control Neighbor’s Conduction

Magnetoresistance is an important material property that is utilized in electronic compasses, hard disk drives, biosensors, and microelectromechanical systems (MEMS). In normal (nonmagnetic) conductors, magnetoresistance is a variation of the resistance that occurs when an external magnetic field influences how electrons flow through the material. In magnetic conductors, the magnetoresistance depends on the magnetization direction. In Physical Review Letters, Hiroyasu Nakayama of Tohoku University, Japan, and co-workers generate a new kind of magnetoresistance in a system with an insulating magnet [1]. The results are independently corroborated and shown to also exist in other materials by Christian Hahn of CEA Saclay (Atomic Energy Commission), France, and his collaborators writing in Physical Review B [2]. These developments may open new applications of insulator spintronics, devices that utilize spin currents in insulating magnets.