Photorefractive effect in LiNbO3 crystals enhanced by stoichiometry control

Abstract

LiNbO 3 single crystals with a composition close to stoichiometry are grown by using a double crucible Czochralski method equipped with an automatic powder supply system. The photorefractive properties are compared with those of LiNbO3 crystals grown from the congruent composition melt. Two beam coupling experiments show that both nondoped and Fe-doped stoichiometric crystals exhibit stronger photorefractive effect than the Fe-doped congruent crystals.

Structure and optical properties of near stoichiometric Ce:LiNbO3 crystals

“…The congruent LiNbO 3 (CLN) has, however, disadvantages such as low response speed and low resistance to photo-damage, which limit their usage for holograph storage [4]. The stoichiometric LiNbO 3 (SLN) crystal shows significant improvement in some photorefractive properties and the response speed of SLN crystals is two orders higher than that of CLN crystals [5,6]. TSSG is a method for the growth of SLN crystals [7].…”

Control of Intrinsic Defects in Lithium Niobate Single Crystal for Optoelectronic Applications

“…into the lattice within a threshold concentration limit reduces the intrinsic defects of the CLN crystals and consequently the damage threshold increases [9,10,[26][27][28][29]52,[61][62][63]. At the same time, some optical properties such as refractive index, electro-optic coefficients, nonlinear optical coefficients, and phase-matching conditions for various configurations of second-harmonic generation (SHG) are influenced by these dopants [18,19]. In the present article Mg has been taken as an example in this context.…”

“…It has generated interest over the years mainly due to its use in nonlinear optical frequency conversion, electro-optical modulation, surface acoustic wave devices, holographic data storage, optical waveguides, and integrated optical applications [11][12][13][14]. In more recent times ferroelectric domain engineering of LN crystal has paved a new pathway for developing periodically poled LiNbO 3 (PPLN) for fabricating optical parametric oscillators (OPO) to generate tunable lasers in the visible and mid-infrared radiation [11,15,16], tandem-poled lithium niobate crystals for the broadband green light source [17], laser projectors or display devices [18], and photonic band gap materials [19]. Further, there is a considerable interest in micro-structuring of LN crystals for their use in the micro-electro-mechanical system (MEMS) [20].…”

Effect of post treatment on the photorefractive properties of Ru‐doped lithium niobate

“…One is adding a small amount of various transition metal ions into LiNbO 3 , such as Fe, Mn, Rh, Cu, Ce and so on [2][3][4][5]. Another is increasing the Li/Nb ratio in LiNbO 3 crystals [6,7]. The other method is employing the proper post treatment process (reduction or oxidation) [8,9].…”