Two-photon readout of three-dimensional memory in silica

We report the readout of three-dimensional (3D) optical memory in silica by detecting the photoluminescence (PL) of the bits (voxels). A broad defect-related PL band at 400–700 nm was excited by two-photon absorption of femtosecond (pulse duration of 120 fs) illumination at 795 nm. We employed a simple reflection-type scanning readout without the use of a confocal detection scheme to read 3D memory by recording the PL of the bits (the same objective lens was used for the excitation and the collection of the PL). Bit plane separation as small as 3 μm was resolved without cross talk, when the theoretical limit of the axial resolution evaluated as a full-width at half maximum measure of a bit size was 1.4 μm at the fabrication conditions employed.

[1]  S Kawata,et al.  Readout of three-dimensional optical memories. , 1996, Optics letters.

[2]  W. Denk,et al.  Two-photon laser scanning fluorescence microscopy. , 1990, Science.

[3]  Y. Kawata,et al.  Reflection-type confocal readout for multilayered optical memory. , 1998, Optics letters.

[4]  S Kawata,et al.  Reflection confocal microscope readout system for three-dimensional photochromic optical data storage. , 1998, Optics letters.

[5]  Saulius Juodkazis,et al.  Three-Dimensional Optical Data Storage in Vitreous Silica , 1998 .

[6]  J. P. Callan,et al.  Three-dimensional optical storage inside transparent materials. , 1996, Optics letters.

[7]  D A Parthenopoulos,et al.  Three-Dimensional Optical Storage Memory , 1989, Science.

[8]  E. Mazur,et al.  Ultrafast-laser driven micro-explosions in transparent materials , 1997 .

[9]  Saulius Juodkazis,et al.  Luminescence and defect formation by visible and near-infrared irradiation of vitreous silica , 1999 .

[10]  Peter G. Kazansky,et al.  Anomalous anisotropic light scattering in Ge-doped silica glass , 1999 .

[11]  Satoshi Kawata,et al.  Comparison of recording densities in three-dimensional optical storage systems: multilayered bit recording versus angularly multiplexed holographic recording , 1996 .

[12]  Saulius Juodkazis,et al.  Optically induced defects in vitreous silica , 2000 .

[13]  S. Paddock,et al.  Confocal laser scanning microscopy. , 1999, BioTechniques.

[14]  Hosono,et al.  Oxygen-related intrinsic defects in glassy SiO2: interstitial ozone molecules , 2000, Physical review letters.

[15]  Saulius Juodkazis,et al.  Transmission and photoluminescence images of three-dimensional memory in vitreous silica , 1999 .