MAGNETIC RECORDING MEDIUM, AND MAGNETIC RECORDING AND REPRODUCING DEVICE

PROBLEM TO BE SOLVED: To provide a bit pattern medium having a ratio (BAR) of linear recording density/track density sufficiently higher than 1, and to provide a magnetic recording and reproducing device wherein a transfer rate can be increased according to surface recording density. SOLUTION: A magnetic disk medium 10 has a nonmagnetic substrate 12, a soft magnetic lining layer (soft magnetic layer) 14, and a magnetic recording layer 16. The magnetic recording layer 16 has annular recesses (grooves) 18 each having a depth reaching the soft magnetic lining layer 14, which form a plurality of annular recording tracks 20. Each recording track 20 has necks (narrowed parts) 22 formed with a predetermined period in a peripheral direction. Each narrowed part 22 has a shape where the end 24 of the recording track 20 is recessed toward the center. A period with which the narrowed parts 22 are formed is a period in which an interval between one narrowed part 22 and another narrowed part 22 is equivalent to a bit length. COPYRIGHT: (C)2011,JPO&INPIT