Emeritus Professor John M Parker
MA PhD FIMMM CEng FSGT
Emeritus Professor of Glass Science and Engineering
Telephone: +44 (0) 114 222 5514
Fax: +44 (0) 114 222 5943
Address: Department of Materials Science and Engineering
Sir Robert Hadfield Building,
Mappin Street, Sheffield, S1 3JD
John Parker moved to Sheffield from the University of Cambridge in 1971, having completed a first class MA in Natural Sciences, a PhD and a post-doctoral NERC fellowship studying aluminosilicates with incommensurate structures. At Sheffield he has developed interests in both the optical/structural properties of glasses and the technology of bulk glass making, supported by a short secondment to a local glass manufacturer in 1975. He is actively involved in the International Commission on Glass, and is past-president of both the Society of Glass Technology and the European Society of Glass Science and Technology.
My key current interests are in glass structural analysis particularly using information derived by optical spectroscopy, and the processes involved in glass crystallisation. Such interests are supporting a project to predict optical spectra based on a knowledge of glass composition, for example for optical filter design; this approach has generated a study of colour control in relation to glass recycling, and the manufacture of low cost UV opaque materials for containers that better protect their contents. It has also led recently to work on coloured pigments for a variety of applications, and a study the art of glass staining in relation to restoration of historic artefacts.
Optically active glasses also present many interesting challenges. For example powder diffraction techniques using both synchrotron (Daresbury) and neutron (CERN) sources, combined with transmission electron microscopy and optical spectroscopy, have been used to study quantum dot development in silicate glasses, and the manufacture of transparent glass-ceramics, in which the precipitated crystalline phase contains an optically active dopant ion e.g. Cr3+:ZnAl2O4 and Er3+:CaF2. Such materials find applications as optical switches, amplifiers, up-converters and photon detectors. A potentially new area of interest is in encryption technologies.
My background in mineralogy has also led to a long-term study of crystalline defects in bulk glass manufacture, many of which arise during melting. This has created extensive industrial interactions and an interest in glass melting reactions; it culminated in the production of a monograph concerning defect identification which is still widely used in the glass industry. I have also worked on the development and characterisation of novel glasses for highly transparent optical fibres based on chalcogenides, fluorides and other halide ions. This has involved studies of glass stability and an identification of sources of defects, as well as an extensive study of the optical spectroscopy of impurity transition metal and rare earth ions.
Throughout my career I have worked closely with industry, and this has included organisations such as British Telecom, Pilkingtons, Johnson Matthey, and Rockware Glass. I have also interacted with the Physics Departments at Sheffield, Brunel and Paisley, and with the Rutherford Appleton Laboratories.
Professional activities and recognition
- A C Hannon & J M Parker, ‘The use of bond-valence parameters in interpreting glass diffraction results’, Phys. Chem Glasses, 43C, 6-12 (2002).
- J Fu, J M Parker, R M Brown, P S Flower, ‘Eu2+ ions in CaF2-containing transparent glass-ceramics’, Mat Res Bull 37, 1843-49 (2002).
- J Fu, J M Parker, R M Brown, P S Flower, ‘Compositional dependence of scintillation yield of glasses with high Gd2O3 concentrations’, J Non-Cryst Solids, 326 & 327, 335-338 (2003).
- J M Parker, ‘Inorganic glasses and their interaction with light’, Rev. Prog. Color., 34, 26-38 (2004).
- J M Parker, ‘Glasses’, Encyclopaedia of Condensed Matter Physics, Ed by F G Bassani, G L Liedl, P Wyder, publ. Elsevier, p273-280, ISBN 0-12-227610-8 (2005).
- J G Fisher, P F James, J M Parker, ‘Soda lime zirconia silicate glasses as prospective hosts for zirconia-containing radioactive wastes’, J Non-Cryst. Solids, 351(8-9), 623-631 (2005).
- P A Bingham, J M Parker, T Searle, I Smith, ‘Local structure and medium range ordering of tetrahedrally coordinated Fe3+ ions in alkali – alkaline earth – silica glasses’, J Non-Cryst Solids, 353(24-25), 2479-2494 (2007).