Amorphous and Nanostructured Chalcogenides

Abstract

After the discovery by B. T. Kolomiets of amorphous chalcogenide semiconductors, these materials were intensely studied by various groups around the world, initially in East and Central European countries. The names of pioneers of amorphous chalcogenides, who laid the cornerstones of the field, include Radu Grigorovici, Jan Tauc, Stan Ovshinsky. In 1977, a Nobel Prize was awarded to Sir Nevill Mott and P. W. Anderson. Since then, the interest in these materials has never decreased. They found numerous industrial applications such as in phase-change memories, optical fibers, sensors etc. In recent years the interest to these materials was re-ignited due to topological insulator properies of Te-based crystals. Scientists and engineers from around the world regularly get together to discuss the latest progress at numerous meetings, the International Conference on Amorphous and Nanocrystalline Semiconductors (ICANS) has seen last year its 50-year anniversary. The two Feature Articles and six Original Papers included in this Topical Section of pss(b) have been specially written by invited speakers of the International Conference “Amorphous and Nanostructured Chalcogenides – Fundamentals and Applicastions (ANC-6)”, held in Brasov, Romania, 24–28 June 2013. The ANC Conference Series funded by Professor Radu Grigorovici, started in 2001 with ANC-1 in Bucharest, followed by conferences 2005 in Sinaia, 2007 in Brasov, 2009 in Constanta and 2011 in Bucharest. The last conference, 2013 in Brasov, gathered scientists from all around the world who are working in the field of structure, properties and applications of amorphous and nanostructured chalcogenides. Around 80 participants (physicists, chemists and engineers) debated, along the 5 days of the conference, the leading problems of amorphous chalcogenides. The next ANC Conference (ANC-7) will be held in Cluj, Transylvania, 5–10 July 2015. The contributions in this Topical Section cover a broad range of issues ranging from basic science, discussing the role of electronic excitation in the phase-change process, to applications of chalcogenides in sensors and solar cells. The Feature Article by Alexander V. Kolobov et al. 1 discusses the athermal amorphization of crystallized chalcogenide glasses and phase-change alloys. In the second Feature Article, Jatin Rath et al. 2 treat problems of the fabrication of SnS quantum dots for solar cell application, i.e. issues of capping and doping. R. Bhageria et al. 3 treat the fragility and molar volumes of non-stoichiometric chalcogenides and discuss the crucial role of melt/glass homogenization. E. Petrakovschi et al. 4 discuss the synthesis of GeSe4 glass by mechanical alloying and sintering. M. Popescu et al. 5 show how chalcogenide systems at the border of the glass-formation domain maximize the switching properties of the chalcogenide amorphous compositions in various ternary systems. M. L. Ciurea et al. 6 discuss the electrical properties related to the structure of GeSi nanostructured films. M. S. Ailavajhala et al. 7 show the sensitivity to radiation of thin Ge–Se films. Finally, M. L. Trunov et al. 8 develop an interesting and modern subject: light-induced mass transport in amorphous chalcogenides, contributing to further progress in surface plasmon-assisted nanolithography and near-field nanoimaging. We thank the authors who dedicated their time to prepare this special selection. Mihai Popescu (Chairman of the ANC-6 Conference) Alexander V. Kolobov