The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 01, 2014
Filed:
Feb. 24, 2012
Masukazu Igarashi, Kawagoe, JP;
Masato Matsubara, Yokohama, JP;
Keiichi Nagasaka, Isehara, JP;
Masato Shiimoto, Odawara, JP;
Masukazu Igarashi, Kawagoe, JP;
Masato Matsubara, Yokohama, JP;
Keiichi Nagasaka, Isehara, JP;
Masato Shiimoto, Odawara, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A spin torque oscillator for microwave assisted recording includes a perpendicular free layer having a magnetic anisotropy axis in a direction perpendicular to a film surface, and an in-plane free layer composed of a magnetic film effectively having a magnetization easy plane on a film surface. When electric currents flows from the in-plane free layer side to the perpendicular free layer side, both free layers exchange spin information and thereby rotate their respective magnetizations almost antiparallel to each other and along a boundary surface with high-speed. Preferably, the perpendicular free layer is thinner than the in-plane free layer. It is also preferable that a magnetic anisotropy field of the perpendicular free layer attributable to materials should balance, in reverse directions, with an effective demagnetizing field in the perpendicular direction. Furthermore, the perpendicular free layer is preferably placed on the main pole side.