| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a microwave assisted magnetic recording medium in which writing can be performed by a high frequency magnetic field of lower frequency than a ferromagnetic resonance frequency of a recording layer. <P>SOLUTION: A microwave assisted magnetic recording medium 10 comprises: a substrate 1; a base layer 2 formed on the substrate 1; a soft magnetic layer 4, a recording layer 3 and a protective layer 5 formed on the base layer 2. A reversal magnetic field of the recording layer 3 is controlled by a spin wave induced in the soft magnetic layer 4. Since the soft magnetic layer 4 has a spin wave frequency lower than the ferromagnetic resonance frequency of the recording layer 3, writing can be performed by the high frequency magnetic field having lower frequency. When the recording layer 3 has a magnetic anisotropy of 5×10<SP POS="POST">5</SP>J/m<SP POS="POST">3</SP>or greater and a thickness of 20 nm or less, and the soft magnetic layer 4 has a magnetic anisotropy of 5×10<SP POS="POST">5</SP>J/m<SP POS="POST">3</SP>or less and a thickness of 20 nm to 150 nm, the spin wave is propagated into the recording layer by a high frequency magnetic field of 1 GHz to 15 GHz, thereby significantly reducing a magnetic coercive force of the recording layer. <P>COPYRIGHT: (C)2013,JPO&INPIT |
