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Multilayered optical memory with bits stored as refractive index change. III. Numerical results of a conventional multilayered optical memory

Shanghai Key Laboratory of Contemporary Optics System, College of Optics and Electronic Information Engineering, University of Shanghai for Science and Technology, Shanghai, China.
Journal of the Optical Society of America A (Impact Factor: 1.45). 08/2008; 25(7):1810-9. DOI: 10.1364/JOSAA.25.001810
Source: PubMed

ABSTRACT In terms of the electromagnetic theories described in Part I of our current investigations [J. Opt. Soc. Am. A24, 1776 (2007)] and in [Opt. Express 16, 2797 (2008)], the characteristics of the cross talk and the modulation contrast and the variation of the power of the readout signals with the scanning position along the track are investigated in detail by computer simulations for a conventional multilayered optical memory (CMOM), where the two cases, i.e., the storage medium being homogenous and planar stratified homogenous, are considered. Results show that the feature sizes of bits, the distances between the two adjacent tracks, and the thickness of layers have significant effects on the cross talk and the modulation contrast. The polarization of the reading light also has significant effects on the cross talk, whereas it has only slight effects on the modulation contrast. Moreover, for a CMOM, the optimal polarization of the reading light is suggested.

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