(Optical Society of America, 1996) Glezer, E. N.; Milosavljevic, M.; Huang, L.; Finlay, R. J.; Her, T. -H.; Callan, J. P.; Mazur, Eric
We present a novel method for three-dimensional optical data storage that has submicrometer size resolution, provides a large contrast in index of refraction, and is applicable to a wide range of transparent materials. Bits are recorded by use of a 0.65-N.A. objective to focus 100-fs laser pulses inside the material. The laser pulse produces a submicrometer-diameter structurally altered region with high contrast in index of refraction. We record binary information by writing such bits in multiple planes and read it out with a microscope objective with a short depth of field. We demonstrate data storage and retrieval with 2-μm in-plane bit spacing and 15-μm interplane spacing (17 Gbits/cm^3). Scanning electron microscopy and atomic force microscopy show structural changes confined to an area 200 nm in diameter.
