4th Generation Optical Memories Based on Super-resolution Near-field structure (Super-RENS) and Near-field Optics
Phase-change materials have additional potential for future nanotechnological devices besides their applications in optical disks and solid-state memory devices. When comparing the crystalline state and amorphous state, phasechange materials usually have two distinctly different refractive indices. Especially, one phase shows a positive dielectric constant, while the other one shows a negative constant. Once these phases exist together with a boundary on the nanometer length scale, the optical contrast can be used to produce localized plasmons there. Such a condition can be generated by focusing a laser beam on thin multilayer stacks. This is called super-resolution near-field structure (super-RENS). Since its invention in 1998, ultra-high density optical storage system based on this principle has been developed. In this chapter, the basic concept of plasmons and near-field optics, multilayer design, and the physical background this technology is based on in phase-change films are discussed.
KeywordsLaser Spot Diffraction Limit Phase Change Memory Recording Layer Optical Aperture
Unable to display preview. Download preview PDF.
- [13.3]Born B. and Wolf E. :Principles of Optics, Cambridge (1999)Google Scholar
- [13.4]Paesler M. and Moyer P.: Near-field optics- Theory, Instrumentation, and Applications, John Willey & Sons (1996)Google Scholar
- [13.5]Shalaev V. M. and Kawata S.: Nanophotonics with Surface plasmons, Elsevier (2007)Google Scholar
- [13.6]Raether H.: Surface Plasmons – on smooth and rough surfaces and on gratings. Springer (1988)Google Scholar
- [13.8]Tominaga J. and Nakano T.: Optical near-field recording – science and technology. Springer (2005)Google Scholar
- [13.17]CASTEP code: Materials Studio 4.2. Accelrys. Com.Google Scholar
- [13.19]Tominaga J., Fons P., Shima T., Kurihara K., Nakano T., Kolobov A. and Petit S.: Localized light focusing and super-resolution readout via chalcogenide thin film. Mater. Rec. Soc. Symp. Proc. 918, 41-51 (2006)Google Scholar