High Resolution XRD Studies on Mg, Cr and Nd Doped LiNbO3 Crystals
Undoped and doped LiNbO3 single crystals were grown by Czochralski technique. Comparative studies on these undoped, Cr doped, Mg doped, Mg:Cr codoped and Mg:Nd codoped LiNbO3 single crystals were carried out. Phase identification was done using powder XRD technique. The effect of doping and co-doping on crystalline perfection of these crystals was monitored using high resolution x-ray diffraction (HRXRD) technique. The diffraction curves (DCs) were recorded in symmetrical Bragg geometry for (006) diffracting planes using MoK￻ 1 radiation. tant is co-doping with Mg or Zn at a level above 4.5 mol%, which inhibits photorefractive properties of the material. Another potential application of LiNbO3 is in Nd 3+ based compact diode-pumped self-frequency doubled lasers that emit green radiation, useful for applications in optical data storage, and excitation sources to replace ion gas lasers and pumping of parametric oscillators and amplifiers (10). The
Ti-atom disorder in Th+ x S2 crystals
Abstract Titanium disulphide single crystals (Ti1+x S2) containing an excess of titanium have been grown and investigated to determine the atomic arrangement to the excess Ti atoms and their influence on the electrical properties of the crystals. The excess atoms lie in a Van der Waals gap which imposes short-range order on the atoms, but an anomaly in the resistance at low temperatures and diffuse scattering as seen in electron diffraction patterns are attributed to long-range disorder amongst the Ti atoms.
The measuriment of ferromagnets magnetic characteristics using Labview software
The digital method of measurement and registration of dynamic loops hysteresis family of magneto-soft materials where, along with known analogues from electro-technical steel, magnetic materials with considerably smaller specific magnetic losses such as amorphous alloys on the basis of iron, is offered. Tests of magnetic properties of materials are carried out on the base of the hardware-software measuring complex in which along with the standard established electric equipment and USB oscillograph for realization of a digital method, the software for the personal computer developed in the environment of visual programming of Borland Delphi 7.0, connected through the ActieveX technology with the Labview 7.0 environment, is applied. The software allows carrying out input of basic data concerning geometry of prototypes of cores from magnetic materials and numbers of rounds of the magnetizing and measuring windings located on their surface. Experimental data on voltage at measuring winding terminals are processed by means of the virtual integrator in a Labview package. The developed software provides the possibility of saving the obtained hysteresis loop in the form of a text file, and creation of the hysteresis loops family on the virtual oscillograph screen.