PURPOSE: To decrease a substantial contact area and to prevent sticking at the time of stopping and the failure of a magnetic head element for magnetic field modulation and a magneto-optical disk by specifying the surface roughness of the surface of a slider incorporating the magnetic head element opposed to the magnet optical dish within a range of the specific value of the max. height.

CONSTITUTION: The slider 7 into which the magnetic head element for magnetic field modulation is incorporated is formed into a slider shape by cutting out a material substrate consisting of Mn-Zn ferrite, calcium titanate, etc. A grinding wheel to be used at this time is formed to have adequate roughness so that the surface roughness of the cut-out surface as the max. height Rmax attains 0.20μm≤Rmax≤2μm. This cut-out surface is formed as the surface 7a facing the magneto-optical disk 8 constituted by forming a recording part 5 consisting of a magnetic recording layer 3, a reflection layer 4 and a dielectric layer 2 and a protective layer 6 on a transparent substrate 1. As a result, the substantial contact area of the surface 7a of the slider 7 and the disk 8 is decreased. The sticking of both in the stopping state and the failure of the magnetic head element and the disk 8 are thus prevented.