Low-Power Terahertz Magnetic Nano-oscillators

摘要

A magnetic nano-oscillator according to an embodiment of the present invention comprises: a ferromagnetic layer disposed on a substrate; a nonmagnetic conductive layer laminated on the ferromagnetic layer; an antiferromagnetic layer (or ferrimagnetic layer) stacked on the nonmagnetic conductive layer; and first and second electrodes in contact with both side surfaces of the ferromagnetic layer and the nonmagnetic conductive layer, respectively. The antiferromagnetic layer (or ferrimagnetic layer) is a thin film made of a material that is magnetized in a direction perpendicular to or horizontal to a film surface. The ferromagnetic layer is magnetized in a horizontal direction on the film surface of the ferromagnetic layer, and the in-plane current injected into the ferromagnetic layer and the nonmagnetic conductive layer through the first and second electrodes provides a spin current including spin in the thickness direction of the thin film transferred to the antiferromagnetic layer (or ferrimagnetic layer). The magnetization precession of the sublattice of the antiferromagnetic layer (or ferrimagnetic layer) is generated. According to the present invention, low current density and frequency tunability can be improved.