Showa Denko K.k.

Japan Science and Technology Agency

Akita University

Shunji Ishio

Hitoshi Saito

Takashi Hasegawa

Iwao Okamoto

Naoya Yamamoto

A magnetic recording medium for use in digital magnetic recording, which comprises a nonmagnetic substrate having deposited thereon a magnetic layer, wherein with respect to the in-plane direction, the magnetic recording layer comprises a plurality of ferromagnetic regions separated from each other by an antiferromagnetic region. A production method of the magnetic recording medium and a magnetic disc apparatus are also disclosed.

Magnetic recording medium, production method thereof and magnetic disc apparatus

A coersive force distribution analyzing, apparatus applies a magnetic field substantially perpendicularly to a sample including a perpendicularly magnetically recordable magnetic thin film. While tow-dimensionally moving the sample, the coersive force distribution analyzing apparatus generates a magnetic flux detection signal in response to a leakage flux generated in a magnetic domain on a sample surface. The apparatus applies, to the sample, a first external magnetic field and a second external magnetic field respectively corresponding to a first threshold and a second threshold selected from a hysteresis characteristic corresponding to average magnetization of the sample. This results in first magnetic domain image data and second magnetic domain image data. The apparatus uses the first and second thresholds to binarize the first and second image data to generate a first coersive force distribution pattern corresponding to the difference between the binarized first and second image data.

Method and device for analyzing distribution of coercive force in vertical magnetic recording medium using magnetic force microscope

Growing community of inventors

Akita, Japan

Shunji Ishio