Open AccessOptical data encryption using time-dependent dynamics of refractive index changes in LiNbO_3
Author(s) -
Daniel Sando,
Esa Jaatinen
Publication year - 2013
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.21.019510
Subject(s) - erasure , photorefractive effect , optics , lithium niobate , refractive index , encryption , degradation (telecommunications) , materials science , computer science , physics , telecommunications , programming language , operating system
We present a method for optical encryption of information, based on the time-dependent dynamics of writing and erasure of refractive index changes in a bulk lithium niobate medium. Information is written into the photorefractive crystal with a spatially amplitude-modulated laser beam which when overexposed significantly degrades the stored data making it unrecognizable. We show that the degradation can be reversed and that a one-to-one relationship exists between the degradation and recovery rates. It is shown that this simple relationship can be used to determine the erasure time required for decrypting the scrambled index patterns. In addition, this method could be used as a straightforward general technique for determining characteristic writing and erasure rates in photorefractive media.