All-optical nanoscale read∕write bit formation

Abstract

The rapid development of optical processing in optical circuitry (optical computing) is spawning the need for fully optical nonvolatile memory schemes. Nonvolatile memory schemes typically involve diffraction-limited writing techniques like those found in high-density DVDs and CDs. This need limits their memory density by placing a lower boundary on bit size, which is determined by the wavelength of light used in writing the bit. Using near-field optics can provide a revolutionary approach to optical storage, breaking the diffraction limit by a factor of 10, allowing for significantly enhanced data densities. In this approach, the high-frequency components of the near field are used "to write" information in nanostructured composite ultra-thin films with feature sizes of 200 nm. Fully optical readouts are possible at data densities approaching 100 MBits/mm2. Because of the all-optical nature of this technique, this method can be fully compatible with the next generation of optical computing platforms. It is anticipated that through this research program, this approach will open new vistas in the creation of subwavelength optical circuits, optical processing, and optical data storage.