Tuesday, January 12, 2016

Seminar: "Transparent glass-ceramics for photonics applications produced by melting and sol-gel" by Dr. Maria Jesus Pascual 1.21.16/11:00am-12:00pm/ CREOL RM 103

Seminar: "Transparent glass-ceramics for photonics applications produced by melting and sol-gel" by Dr. Maria Jesus Pascual
Thursday, January 21, 2016 11:00 AM to 12:00 PM
CREOL Room 103

G.Gorni 1, S.Pelli2, J.J. Velázquez1, Y.Castro1 , A.Durán1, R.Balda3, M.J. Pascual1
1Ceramics and Glass Institute (CSIC), Madrid, Spain
2MDF Lab, Applied Physics Institute Nello Carrera (IFAC-CNR), Firenze, Italy
3Applied Physics Dept. I, Superior School of Engineering, Bilbao, Spain

Transparent oxyfluoride nano-glass-ceramics doped with RE ions are very interesting materials for photonics applications. They combine the good mechanical, chemical and thermal stability of oxide glasses with the fluoride crystals, very good host for RE ions and suitable for optical properties due to their low phonon energies. The processing route is a key issue for a suitable preparation of these materials. The typical glass processing method is the melting–quenching (MQ) but the sol-gel (SG) method is a promising alternative. MQ requires high melting temperatures with a limitation in the fluorine content. However, bulk materials and fibers can be easily obtained. SG is a cheap and low-temperature technique that allows a better control of composition and doping level. SG materials have high homogeneity and purity. Thin film can be easily obtained but bulk materials are difficult to prepare and fiber.
Oxyfluoride glass-ceramics with LaF3 nanocrystals obtained by MQ and SG will be presented as study example of the processing parameters. Doping with Pr3+/Yb3+ has been used to study the down-conversion process and also doping with Nd3+ to study the laser emission properties. The crystallization process has been described using DTA taking into account the effect of the dopants. The glass-ceramics were also studied by XRD and HR-TEM. Finally, the relation between processing-structure-optical properties of these materials is discussed.

Doctor in Chemistry (2000) from Autónoma University of Madrid (UAM), Spain. Tenured Scientist in the Glass Department of the Ceramics and Glass Institute (ICV) of the Spanish Research Council (CSIC) since 2007. She has carried post-doctoral stages in Otto-Schott Institute Jena (Germany), RWTH Aachen (Germany), Aveiro University (Portugal), UFSCar and UEPG (Brazil).  Secretary of the Glass Section of the SECV (Spanish Society of Ceramic and Glass) since 2008. Gottardi Prize in 2010 given by the International Commission on Glass (ICG). Current ICG Treasurer.
Research interests:
-                Glasses and glass-ceramics: melting, thermal properties, phase separation, crystallization, sintering…
-               Glass sealing materials for low and high temperature devices.
-               Glass-ceramics with nanocrystals for photonic applications.
Ceramics and Glass Institute (CSIC): www.icv.csic.es
Research group GlaSS: http://glass.icv.csic.es/index.php

For additional information:
Prof. Kathleen Richardson

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