New nanostructured glass for imaging and recording

August 16, 2011

Researchers at the University of Southampton have developed new nano-structured glass, turning it into a new type of computer memory that has applications in optical imaging and recording.

The researchers used nano-structures to develop new monolithic glass space-variant polarization converters. These millimeter-sized devices change the way light travels through glass, generating “whirlpools” of light that can then be read in much the same way as data in optical fibers.

This enables more precise laser material processing, optical manipulation of atom-sized objects, ultra-high resolution imaging and, potentially, table-top particle accelerators. Information can be written, wiped, and rewritten into the molecular structure of the glass using a laser.

At sufficient intensities, ultra-short laser pulses can be used to imprint tiny dots (voxels) in glass. Previous research showed that lasers with fixed polarization produce voxels consisting of a periodic arrangement of ultra-thin (tens of nanometers) planes. By passing polarized light through such a voxel imprinted in silica glass, the researchers observed that it travels differently, depending on the polarization orientation of the light.

The advantage of this approach over existing methods for microscopy is that it is 20 times cheaper and more compact, the researchers said.

Ref.: Martynas Beresna, et al., Radially polarized optical vortex converter created by femtosecond laser nanostructuring of glass, Applied Physics Letters, 2011; 98 (20): 201101 [DOI: 10.1063/1.3590716]