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Lithium Niobate Crystals (lithium + niobate_crystal)

Distribution by Scientific Domains
Physics and Astronomy100%

Selected Abstracts

Electron paramagnetic resonance and electron-nuclear double resonance of nonequivalent Yb3+ centers in stoichiometric lithium niobate

PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 1 2009
Galina Malovichko
Abstract Lithium niobate crystals doped with ytterbium were studied using Electron Paramagnetic Resonance (EPR) and Electron Nuclear Double Resonance (ENDOR). The tremendous narrowing of EPR lines in nearly stoichiometric samples, when compared to those in congruent samples, allowed us to distinguish nine non-equivalent centers, as well as line splitting caused by the hyperfine interaction of ytterbium electrons with the nuclear spins of two magnetic isotopes, 171Yb and 173Yb. Eight of the nine centers are described for the first time. It was found that three of the centers have axial C3 symmetry, and all others have the lowest C1 symmetry due to the presence of intrinsic defects and/or charge compensation defects in the near neighborhood of Yb3+. Characteristics of the g -tensor for all of the centers and hyperfine tensors for axial centers were determined. The ENDOR observations of Nb nuclei in the nearest neighborhood of Yb13+ gave direct evidence that the dominated axial Yb1 center has no charge compensator in its nearest surroundings (distant charge compensation mechanism). Both the EPR and ENDOR data for the main axial ytterbium center are explained by a supposition that Yb3+ ions substitute for Li+. Possible models for low-symmetry centers are discussed. The obtained numerous spectroscopic parameters can be used as cornerstones for model calculations of Yb3+ centers in lithium niobate. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

EPR of Nd3+ in congruent and nearly stoichiometric lithium niobate

PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 2 2006
G. Malovichko
Abstract Lithium niobate crystals doped with neodymium were studied with the help of electron paramagnetic resonance, EPR in the temperature range of 4.2,20 K. Tremendous narrowing of the EPR lines in nearly stoichiometric samples in comparison with congruent ones allowed us to distinguish four non-equivalent centers, as well as line splitting caused by hyperfine interaction of neodymium electrons with nuclear spins of both magnetic isotopes 143Nd and 145Nd. It is shown that one of the centers has axial C3 symmetry, whereas all others have lowest C1 symmetry due to presence of intrinsic defects or/and charge compensation defects in the near neighborhood of Nd3+. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Picosecond optical parametric oscillator pumped synchronously, intracavity, by a mode-locked Nd:YVO4 laser

LASER PHYSICS LETTERS, Issue 2 2007
A. Zavadilová
Abstract The operation of a picosecond synchronously intracavity pumped optical parametric oscillator (OPO) is reported. A magnesium doped lithium niobate crystal (MgO:PPLN), periodically poled, is used as the optical parametric oscillator crystal coupling the pump and the resonant signal cavities. The active medium of the pump cavity is a a diode pumped passively mode-locked Nd:YVO4 crystal. Continuous mode-locked operation was achieved, tunable from 1531 to 1554 nm by adjusting the OPO crystal from 31 to 55°C. The spectral width of the generated radiation was 2 nm. (© 2007 by Astro, Ltd. Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

Cover Picture: Laser & Photon.

LASER & PHOTONICS REVIEWS, Issue 3 2009
Rev. 3(3)/200
Micro-structuring techniques in lithium niobate crystals can lead to unprecedented performance in integrated Mach-Zehnder modulators, including ultra-low voltage and large bandwidth operation. (Picture: D. Janner et al., pp. 301,313, in this issue) [source]