MAGNETIC SUPERRESOLUTION

Magnetically induced super-resolution (MSR) disks have been proposed to overcome the diffraction limit. This paper reports an MSR disk which has exchange-coupled magnetic double layers, An in-plane magnetization film is used as a readout layer in the magnetic double layers. The MSR disk can be overwritten by a magnetic field modulation recording method. An areal density of 2.2 Gbit/in(2) was obtained with a currently available optical head having a 680nm wavelength laser. Besides, the disk had high recorded-data-stability in continuous readout of 5 X 10(5) revolutions with a laser power of 2.5 mW, and it also kept a high signal quality after a continuous erasing test of 2 X 10(5) revolutions with a recording laser power of 6.5 mW.