Photorefractive Materials for Nonvolatile Volume Holographic Data Storage
Lambertus Hesselink,
*
Sergei S. Orlov,
Alice Liu,
Annapoorna Akella,
David Lande,
Ratnakar R. Neurgaonkar
Optically gated recording and nonvolatile readout in a digital
volume holographic data storage system that uses a pair of mutually
incoherent light sources during recording and only one for readout were
demonstrated recently. This approach used stoichiometric lithium
niobate, which after post-growth processing gave rise to an at least
two orders of magnitude improvement in sensitivity over the best
materials reported previously. It is also shown that by adding certain
dopants (iron and manganese) to near-stoichiometric lithium niobate,
the dark storage time and gating efficiency can be increased compared
with previous work. The underlying physical mechanisms of gated
recording and the effectiveness of the gating process responsible for
this manifold improved performance are discussed, and bipolarons and
small polarons are identified as the responsible photorefractive
species.
L. Hesselink, A. Liu, A. Akella, D. Lande, Stanford University,
Stanford, CA 94305, USA. S. S. Orlov, Optitek, 1330 West
Middlefield Road, Mountain View, CA 94043, USA. R. N. Neurgaonkar, Rockwell International Science Center, 1049 Camino dos
Rios, Thousand Oaks, CA 91360, USA.
*
To whom correspondence should be addressed. E-mail:
bert{at}kaos.stanford.edu
All authors contributed equally to this work.
