Glass Reflections
Cambridge 7th to 9th September

Presenting Author:
Stephen Elliott

article posted 15 Apr 2015

Stephen Elliott

Stephen Elliott is Professor of Chemical Physics in the Department of Chemistry at Cambridge University and a Fellow of Trinity College, Cambridge, UK. He has published more than 340 papers in several fundamental areas of glass science such as structure and modelling of amorphous solids, vibrational states of disordered solids, electronic structure of glasses, amorphous chalcogenides, and phase-change materials. He is the author or coauthor of three widely used textbooks ("Physics of Amorphous Materials"; "The Physics and Chemistry of Solids"; and "Optical Non-linearities in Chalcogenide Glasses and their Applications" (with A. Zakery)) - the first one is considered a must-read for all young scientists working in the fundament al aspects of amorphous materials.

Prof. Elliott received his PhD from Cambridge University, UK, working in the Physics and Chemistry of Solids group at the Cavendish Laboratory under the guidance of Professors E.A. Davis and N.F. Mott (a 1977 Nobel Prize in Physics). Prof. Elliott received the prestigious Zachariasen Prize in 1992 given to the researcher aged under 40 who has made the most significant and innovative advances in the field of non-crystalline materials.

In 2001, Prof. Elliott became the very first recipient of the Stanford R. Ovshinsky Award for excellence in non- crystalline chalcogenides. He is or has been an editor or a coeditor or a member of advisory editorial boards of a number of prestigious journals, such as Philosophical Magazine, Philosophical Magazine Letters, Journal of Non- crystalline Solids, Journal of Optoelectronics and Advanced Materials, and European Journal of Pure and Applied Physics. Last year he received the American Ceramic Society George W. Morey Award.

Prof. Elliott has devoted much of his recent work to the understanding of photo-induced effects in amorphous chalcogenides and of chalcogenide Phase-Change Materials (PCMs), which are already used in the manufacture of rewritable optical discs and flash memory in Nokia Asha smartphones. His current research continues in the field of PCMs, examining the microscopic origins of the fast amorphous - crystalline phase transitions, and the design of new PCMs for in-memory logic and neuromorphic computing

Optical- and electrical-induced changes in chalcogenide glasses
Stephen Elliott
Department of Chemistry, University of Cambridge, Cambridge CB2 1EW

Chalcogenide glasses - alloys of Group VI chalcogen elements (S, Se, Te) with other elements, such as As, Ge, Sb etc - can exhibit a variety of transformations to different metastable states. These metastable states can be other amorphous phases or crystalline states. The atomic and electronic structural features of chalcogenide glasses that facilitate such transformations, e.g. low atomic coordination, non-bonding lone-pair p-states forming the top of the valence band, and the close similarity between amorphous and crystalline structures in certain cases, will be discussed. Examples will be given of photo-induced metastability, as well as the ultra-fast (~ns) electrical-induced crystallization characteristic of phase-change materials used in next-generation non-volatile computer memories.