Strontium barium niobate
About: Strontium barium niobate is a research topic. Over the lifetime, 811 publications have been published within this topic receiving 13595 citations.
Papers published on a yearly basis
TL;DR: The Ferroelectric Ba0.27Sr0.75Nb2O5.78 as discussed by the authors is a tungsten bronze-type structure crystallizing in the tetragonal system, with lattice constants a = 12.43024
Abstract: Ferroelectric Ba0.27Sr0.75Nb2O5.78, with Tc = 348° ± 15°K, is a tungsten bronze‐type structure crystallizing in the tetragonal system, with lattice constants a = 12.43024 ± 0.00002 and c = 3.91341 ± 0.00001 A at 298°K, space group P4bm, and five formulas in the unit cell. The integrated intensities of 6781 structure factors were measured with PEXRAD, 875 symmetry‐independent structure factors being significantly above background. The metal‐atom positions were determined from the three‐dimensional Patterson function and the oxygen atoms from subsequent Fourier series. The final agreement factor between measured and calculated structure factors is 0.0508. The structure consists of close‐packed slightly puckered layers of oxygen atoms separated by nearly c / 2. The Nb atoms are slightly displaced from one layer, the Ba and Sr atoms from the other and in the same sense. The oxygen atoms in the Ba and Sr layer are disordered. Neither of the two independent sites occupied by the Ba and Sr atoms is fully filled....
TL;DR: In this paper, the authors measured the coupling of two optical beams in strontium-barium niobate crystals and determined the photorefractive properties: the effective density, sign, and spectral response of the dominant charge carrier, the grating formation rate, dark conductivity, and carrier diffusion length.
Abstract: We have grown and optically characterized strontium‐barium niobate crystals, including both undoped and cerium‐doped crystals having two different Sr/Ba ratios (61/39 and 75/25). By measuring the coupling of two optical beams in the crystals, we have determined the following photorefractive properties: the effective density, sign, and spectral response of the dominant charge carrier, the grating formation rate, dark conductivity, and carrier diffusion length. We find that electrons are the dominant photorefractive charge carriers in all of our samples; the typical density of photorefractive charges is ∼1×1016 cm−3 in the undoped samples. The grating formation rate increases with intensity, with a slope of ∼0.3 cm2/(W s) over an intensity range of ∼1–15 W/cm2 in undoped samples. Cerium doping improves both the charge density (increased by a factor of ∼3) and the response rate per unit intensity (∼5 times faster).
TL;DR: In this article, the system of ferroelectric strontium barium niobates, SrxBa1•xNb2O6, was investigated and linear electrooptic coefficients as large as r ∼ 4 × 10−5 cm/statvolt have been measured.
Abstract: Linear electro‐optic coefficients as large as r ∼ 4 × 10‐5 cm/statvolt have been measured in the system of ferroelectric strontium barium niobates, SrxBa1‐xNb2O6. In the first crystals x varies from 0.75 to 0.25, with Curie temperatures ranging from ∼60°C to 250°C. At 15 Mc, the respective half‐wave field distance products range from 48 to 1236 V.
TL;DR: In this paper, the first observation of two-dimensional steady-state photorefractive solitons with diameters as small as 9.6 mu m at microwatt power levels was reported.
Abstract: The first observation of two-dimensional steady-state photorefractive solitons is reported. Application of an electric field of 5.8 kV/cm to strontium barium niobate yields solitons with diameters as small as 9.6 mu m at microwatt power levels. >
TL;DR: In this paper, the authors used the charge transport model of photorefractivity to evaluate four figures of merit that can be used to characterize the performance of photoresilicon materials.
Abstract: Optimal properties of photorefractive materials for optical data processingGeorge C. Valley and Marvin B. KleinHughes Research Laboratories, 3011 Malibu Canyon Road, Malibu, CA 90265AbstractThe charge transport model of photorefractivity is used to evaluate four figures of meritthat can be used to characterize the performance of photorefractive materials. The figuresof merit are the steady -state index change, the response time, the energy per area to writea grating with one percent diffraction efficiency, and the index change per absorbed energyper unit volume (photorefractive sensitivity). These indices are evaluated as a function ofgrating period and applied external electric field for Bi12SiO20, a fast material with arelatively small electro -optic coefficient and BaTiO3, a slower material with a much largerelectro -optic coefficient. Methods for optimizing the materials are discussed.IntroductionPhotorefractive materials such as lithium niobate (LiNbO3), potassium niobate (KNbO3),'barium titanate (BaTiO3), strontium barium niobate (SBN) and bismuth silicon oxide(Bi12SiO20) are attractive new candidates for real -time optical data processing, (ODP);