Recording and readout mechanisms of super-resolution near-field structure disc with silver oxide layer

Several technologies to increase the densities of optical discs have been proposed. Among them, the super-resolution near-field structure (Super-RENS) technique (J. Tominaga et al., Appl. Phys. Lett. vol. 73, p. 2078, 1998; H. Fuji et al., Jpn. J. Appl. Phys. vol. 39, p. 980, 2000) is attractive because it satisfies both super-high-density recording/readout and removability at the same time. In this study, we have directly observed recorded and readout states of Super-RENS with AgO_x layer by use of transmission electron microscopy (TEM) for the first time. We also have found that the recording and readout mechanisms are different from those which were explained by the terms of crystallization recording and reversible precipitation of Ag particles in an AgO_x matrix.