ABSTRACT
Abstract. A novel magnetoelectronic device consisting of a ferromagnetic metal film and gate electrodes on GaAs/AlGaAs heterostructure has been fabricated and characterized. Magnetization of ferromagnetic metal film is manipulated by external magnetic field which is applied in parallel to the ferromagnetic metal film axis. Magnetic fringe field at the edge of the ferromagnetic metal film gives rise to the Hall voltage, which shows hysteretic behavior upon magnetic field sweep. When negative voltage is applied to the gate electrodes, the Hall voltage has been increased. The Hall voltage can be amplified by a factor more than 200. 1
1. Introduction Spintronic or Magnetoelectronic devices using ferromagnetic metal films have been one of emerging subjects because of their importance in device applications and their rich fundamental physics. Ferromagnetic metallic films are easily deposited on the surface of other materials. They are easily applicable to devices incorporating various types of materials such as nonmagnetic metal films, superconductors and semiconductors. Moreover, the advantages of ferromagnetic metal films include easy manipulation of magnetization and robust ferromagnetism even in the size of submicron scales. Therefore, ferromagnetic metallic films are widely utilized for manipulation of spins of electrons in spintronic or magnetoelectronic devices.
