Laboratory of preparation of optical materials and thermal analysis
Research team:
Karel Nitsch, Miroslava Rodová, Antonín Cihlář, Robert Král
Scope
Searching for and preparation of materials - crystals, epitaxial layers, nanostructures and glasses - of high quality and purity with interesting optical properties and with their possible application in laser hosts in near IR range, as neutrons, gama and X-rays radiations detectors in industrial and medical application.
Preparation of model crystalline systems for luminescence mechanism study.
Thermal analysis study of properties of solids and glasses prepared by rapid cooling.
Research and development in the field of materials preparation
Materials studied:
Halides crystals - chlorides, bromides and iodides (pure and doped by transient metals and metals of rare earth) alkaline - Na, K, Rb, Cs, lead PbX2 (X - Cl, Br, I), double alkali- lead - KPb2Cl5, CsPbCl3, CsPbBr3, RbPb2Cl5, RbPb2Br5.
Epitaxial layers - aluminum and iron rare earth garnet.
Phosphate glasses - double phosphates (PO3)-
of alkali metals (Li, Na, K, Cs) and metals of rare earth
(Y, Ce, Gd, Pr. La)
doped by (Ce, Er, Pr, Yb ...).
Experimental method: Preparation:
starting materials of high purity by means of chemical methods and zone refining
single crystals from the melt by the Bridgman method
single crystals from the high temperature solutions
phosphate glasses
garnet epitaxial layers by LPE (cooperation with Dr. M. Kučera, Faculty of Mathematics and Physics, Charles University Praha)
Study and optimization of crystal growth conditions:
Study of molten state influence (characterized by the thermal treatment and thermal history of the melt)
Study of influence of growth conditions and temperature field in the furnace and in the ampoule on the crystal quality.
Characterization methods:
Characterization of state of the melt using electric resistance measurements
determination of supercooling
Research in the field of thermal analysis
DTA, DSC, TMATermická analýza – materials purity control, determinations of phase transitions, construction of phase diagrams, thermal properties of the glasses, crystallization study of glasses, measurement of glassy melts viscosity using penetration method.
Thermomicroscopy – study of glassy melts nucleation and crystallization
