Nonvolatile two-color holographic recording in nondoped near-stoichiometric lithium tantalate crystals with continuous-wave lasers

Abstract

Nonvolatile holograms have been recorded in nondoped near-stoichiometric LiTaO3 crystals by use of a near infrared (IR) laser for writing and a ultraviolet beam as a gating source. This material exhibits good overall two-color holographic recording characteristics including a high sensitivity of 0.086 cm/J with a gating intensity of 1 W/cm2 at 350 nm, a large refractive index change of as much as 1×10−4, a high resistance to IR erasure, and a long hologram lifetime of five years. The sensitivity can be further enhanced using writing and gating beams of a shorter wavelength without sacrificing readout nonvolatility.