Spectroscopic Properties of TmF-Doped CaF Crystals.

In this study, we report the growth and comprehensive spectroscopic analysis of TmF-doped CaF crystals, grown using the vertical Bridgman method. The optical absorption and photoluminescence properties of both trivalent (Tm) and divalent (Tm) thulium ions were investigated. Optical absorption spectra in the UV-VIS-NIR range reveal characteristic transitions of Tm ions, as well as weaker absorption bands corresponding to Tm ions.

Magnetic Field Effects Induced in Electrical Devices Based on Cotton Fiber Composites, Carbonyl Iron Microparticles and Barium Titanate Nanoparticles.

This work consists in the process of preparing magnetic active composite materials based on cotton fibers, iron carbonyl microparticles and barium titanate nanoparticles, and the electrical devices manufactured with them. For different compositions of the aforementioned ingredients, three such composites are manufactured and compacted at constant pressure between two electrodes. In the absence and in the presence of a magnetic field, using an RLC bridge, magnetocapacitive, magnetoresistive and magnetopiezoelectric effects are highlighted in the custom fabricated devices.