Glass - Back to the Future!

Presenting Author:
Christian Rüssel

article posted 06 Feb 2016

Christian Rüssel studied chemistry in Erlangen University and made a PhD in Physical Chemistry in 1983. Then he joined the Fraunhofer Society Freiburg and in 1984 the Institute of Werkstoffwissenschaften (Glass and Ceramics) in Erlangen. He completed his Habilitation in 1991 (Dr.-Ing. Habil.) and is full professor of Glass Chemistry at the Otto-Schott-Institut of Jena University since 1992. Since 2014 he is Dr. h.c. of the University of Chemical Technology and Metallurgy in Sofia, Bulgaria. He is author or co-author of 440 scientific publications (web of science). His main research areas are glass ceramics and glasses for Optics and Photonics.

New Alumosilicate Glasses for High Performance Laser Applications

Christian Rüssel*, Andreas Herrmann, Stefan Kuhn, Mirko Tiegel
Otto-Schott-Institut, Jena University, Fraunhoferstr. 6, 07743 Jena, Germany

Aluminosilicate glasses usually possess good mechanical and thermomechanical properties. The technology for their fabrication and also their mass production is well established. They are prepared from inexpensive raw materials and the solubility of rare earth oxides is large. By contrast to conventional laser glasses such as phosphate or fluorophosphates glasses, they possess much smaller coefficients of thermal expansion and advantageous mechanical properties.

Numerous rare earth doped alumosilicate glasses were prepared and their thermomechanical and optical properties were measured. The coefficient of thermal expansion as well as the fluorescence lifetime strongly depends on temperature. Furthermore, the concentration of water dissolved in the glass is decisive for the fluorescence lifetime. This was especially illustrated for Yb3+ doped glasses. Various techniques for the minimization of the water concentration were applied and the dependency of the fluorescence on the water concentration examined.

The laser performance of the alumosilicate glasses was tested; it is further shown that the amplification profiles are broader and the damage threshold higher than in conventional laser glasses.