Magnetic recording medium for thermally assisted magnetic recording

A magnetic recording medium used for thermally assisted magnetic recording system provided with

• a substrate configured by glass,
• a heat radiation layer provided on said substrate,
• a heat retention layer provided on said heat radiation layer, and
• a recording layer provided on said heat retention layer via an intermediate layer;
• and
• said heat retention layer configured by a member having an effective refractive index lower than the effective refractive index of said recording layer and having a temperature diffusion coefficient determined by a specific heat, density, and heat conductivity rate higher than glass and lower than a metal, and
• wherein a temperature diffusion coefficient of the member configuring said heat retention layer is made higher than glass and lower than a metal using a temperature diffusion coefficient changing means for changing a ratio of materials configuring this heat retention lager or a density of the same;
• wherein as the material of the member configuring said heat retention layer, a nonmagnetic material with a refractive index of n<1 at the wavelength of a laser beam and, as said temperature diffusion coefficient changing means, a granular structure with pores able to change the density is used.

A magnetic recording medium used for thermally assisted magnetic recording system provided with

• a substrate configured by glass,
• a heat radiation layer provided on said substrate,
• a heat retention layer provided on said heat radiation layer, and
• a recording layer provided on said heat retention layer via an intermediate layer;
• and
• said heat retention layer configured by a member having an effective refractive index lower than the effective refractive index of said recording layer and having a temperature diffusion coefficient determined by a specific heat, density, and heat conductivity rate higher than glass and lower than a metal, and
• wherein
• as the material of the member configuring said heat retention layer, a continuous single layer film of ZrN or In annealed to give a refractive index n≦1 of is used.