Crystal Structure, Luminescence and Electrical Conductivity of Pure and Mg-Doped β-GaO-InO Solid Solutions Synthesized in Oxygen or Argon Atmospheres.

Undoped and Mg-doped β-GaO-20% InO solid solution microcrystalline samples were synthesized using the high-temperature solid-state chemical reaction method to investigate the influence of native defects on structural, luminescent, and electrical properties. The synthesis process involved varying the oxygen partial pressure by synthesizing samples in either an oxygen or argon atmosphere. X-ray diffraction (XRD) analysis confirmed the monoclinic structure of the samples with the lattice parameters and unit cell volume fitting well to the general trends of the (GaIn)O solid solution series.

Gap-Free Tuning of Second and Third Harmonic Generation in Mechanochemically Synthesized Nanocrystalline LiNbTaO (0 ≤ ≤ 1) Studied with Nonlinear Diffuse Femtosecond-Pulse Reflectometry.

The tuning of second (SHG) and third (THG) harmonic emission is studied in the model system LiNb 1-xTa xO 3 (0≤x≤1, LNT) between the established edge compositions lithium niobate (LiNbO 3, x=0, LN) and lithium tantalate (LiTaO 3, x=1, LT). Thus, the existence of optical nonlinearities of the second and third order is demonstrated in the ferroelectric solid solution system, and the question about the suitability of LNT in the field of nonlinear and quantum optics, in particular as a promising nonlinear optical material for frequency conversion with tunable composition, is addressed. For this purpose, harmonic generation is studied in nanosized crystallites of mechanochemically synthesized LNT using nonlinear diffuse reflectometry with wavelength-tunable fundamental femtosecond laser pulses from 1200 nm to 2000 nm.

Chemical Tuning, Pressure, and Temperature Behavior of Mn Photoluminescence in GaO-AlO Alloys.

In this study, we carried out a detailed investigation of the photoluminescence of Mn in GaO-AlO solid solutions as a function of the chemical composition, temperature, and hydrostatic pressure. For this purpose, a series of (AlGa)O:Mn,Mg phosphors ( = 0, ..

AlO co-doped with Cr and Mn, a dual-emitter probe for multimodal non-contact luminescence thermometry.

Luminescence probes that facilitate multimodal non-contact measurements of temperature are of particular interest due to the possibility of cross-referencing results across different readout techniques. This intrinsic referencing is an essential addition that enhances accuracy and reliability of the technique. A further enhancement of sensor performance can be achieved by using two luminescent ions acting as independent emitters, thereby adding in-built redundancy to non-contact temperature sensing, using a single readout technique.

Anomalous Thermal Expansion of HoCoCrO Probed by X-ray Synchrotron Powder Diffraction.

Mixed holmium cobaltite-chromite HoCoCrO with orthorhombic perovskite structure (structure type GdFeO, space group Pbnm) was obtained by solid state reaction of corresponding oxides in air at 1373 K. Room- and high-temperature structural parameters were derived from high-resolution X-ray synchrotron powder diffraction data collected in situ in the temperature range of 300-1140 K. Analysis of the results obtained revealed anomalous thermal expansion of HoCoCrO, which is reflected in a sigmoidal temperature dependence of the unit cell parameters and in abnormal increase of the thermal expansion coefficients with a broad maxima near 900 K.