An optical recording medium includes a crystallizing layer for enhancing
the crystallization of a phase change memory layer, an energy storage
layer for aiding the state transformations of a phase change memory
layer, and/or a modifying element for increasing absorption and contrast
at short wavelengths. An optical data storage and retrieval system
containing same. Also a light-plasmon coupling lens including an
optically transparent substrate having a light incident surface and a
light-plasmon coupling surface opposite the light incident surface. The
light-plasmon coupling surface including at least a set of circular
concentric peaks/valleys which form a Fourier sinusoidal pattern in the
radial direction of the circular concentric peaks/valleys. A conformal
layer of metal is deposited on the light-plasmon coupling surface of the
substrate and has aperture at the center of thereof through which
plasmons are transmitted.