题目：Designer chalcogenides

时间：2016年4月13日（周三）下午3:00-5:00

地点：行政楼111会议室

报告人：Robert E. Simpson

Abstract

Chalcogenides are a class of materials that contain S, Se, or Te. They tend to exhibit a range of particularly interesting functional properties that have wide technological applications. For example phase change chalcogenides have been commercialised in electrical data storage devices and rewriteable optical media, while a number of selenide and telluride compositions are being investigated for application in thin film photovoltaics.

Here I will discuss new ways to design the nanostructure of chalcogenide materials to achieve bespoke functional properties. In this talk I will demonstrate how these methods have allowed us tailor the properties of van der Waals heterostructure superlattices that are composed of two-dimensional chalcogenide crystals, uncover a new model to explain diffusive atomic switching in these superlattices, and design bespoke superlattice structures with optimal properties. Finally I will demonstrate that when ‘designed’  phase change materials are incorporated into prototype memory cells, the memory characteristics exhibit substantial improvements over unstructured alloys of the same composition.

Biography

Rob is currently an Assistant Professor at the Singapore University of Technology and Design (SUTD), where he runs the Advanced Chalcogenides Technologies and Applications Lab (www.ACTALab.com). Rob’s research interests are focussed on designing chalcogenides and applying them to applications in electronics, photonics, and data storage. Prior to joining SUTD Rob received his PhD from from the Optoelectronics Research Centre at the University of Southampton, spent 3.5 years at the Japanese national institute for Applied Industrial Science and technology (AIST) as a JSPS postdoctoral fellow, and one year at the Institut de Ciencies Fotoniques (ICFO), Barcelona. Rob’s research has been awarded a number of prizes including the Westminster medal and the AIST best paper award.