Dr. Mario Affatigato, Professor in Physics Department at Coe College will give a seminar titled "The Electronic Conductivity of Vanadate Glasses, and Some Glassmaking With Levitation" to the interested faculty and students at Discovery Park.

Abstract

Electronically conducting glasses have recently become more important due to their use in detectors. We report on our work developing vanadate glass families that can be tailored to achieve specific values of electronic conductivity. The focus will be on controlling the ratio of V4+/V5+ through the use of additive modifiers (like elemental tellurium); melting atmospheres; and other preparation conditions. Conductivity results were attained over a span of temperatures up to 200 °C. The samples were structurally characterized using FTIR, Raman, EPR, XRD, and colorimetry (for V4+ measurements). The results are also compared to previous work that indicated an optimal V4+ concentration that varied from the 50% mark and are also placed in the context of various “hopping” conductivity models. We also report on glass ceramics and other modifications of vanadium-based glasses. Some of the reported glasses were mounted on prototype detectors and tested at the Fermi National Accelerator facility and at CERN, and we discuss their improved efficiency under various beam conditions. We will also discuss our separate work using aerolevitation to manufacture glasses at high temperatures and under non-equilibrium conditions

This work was supported by Argonne National Laboratory under contract 3F-32104, by the National Science Foundation through grants DMR-CER-1407404, DMR-CER-2203142, and DMR-CER-1746230.

Bio

Prof. Mario Affatigato obtained his undergraduate degree from Coe College in 1989, followed by his Ph.D. from Vanderbilt University in 1995. He has developed a research effort primarily investigating the relationship between the optical properties and structure of glassy materials. He has worked with over 90 undergraduates in projects that include laser-induced modification and exotic manufacturing methods like aerolevitation. His research primarily deals with oxide glasses, especially vanadates, borates, and samples with heavy metals. Prof. Affatigato is a past recipient of the APS Prize for Research at an Undergraduate Institution, a PECASE award from the National Science Foundation (NSF), a SEED Award from the Research Corporation, as well as other research grants from industry, NSF and the Research Corporation. He is a fellow of the American Ceramic Society and the UK Society of Glass Technology, and a Research Corporation Cottrell Scholar. Currently he holds the Fran Allison and Francis Halpin Professorship at Coe College, is the Editor in Chief of the International Journal of Applied Glass Science, and in October will start his term as the President of the American Ceramic Society for 2025-26.