Mork Family Department Graduate Seminar
Friday, Aug 11, 2017 @ 10AM – 11AM
Location: HED 116
Audiences: Everyone is Invited
Host: Paulo Branicio
Active electronic and photonic materials by nanostructural design
Robert Simpson
Singapore University of Technology and Design, Singapore
e-mail: website: http://www.actalab.com
Abstract
Francis Crick famously remarked “If you want to understand function, study structure”. The properties and functions of all materials result from their atomic arrangements. Here I will discuss new ways to design the nanostructure of chalcogenide materials to achieve bespoke functional properties. The characteristics of chalcogenide materials are often optimized by inefficient Edison-style methodologies, where useful properties are occasional serendipitous discoveries rather than designed to specification. In contrast, I will discuss a generalizable approach to optimize the design of materials for application in data storage, photonics, and electronics. In particular I will demonstrate methods that are based on strain engineering and evolutionary approaches to design chalcogenide superlattices. I will show how these methods have allowed us to introduce atomic switching into van der Waals heterostructure superlattices that are composed of two different two- dimensional chalcogenide crystals. 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. Finally, I will discuss the design of new active materials for a range of applications including displays, pollution sensors, and single photon sources.
Biography
Robert Simpson is currently an assistant professor at the Singapore University of Technology and Design (www.sutd.edu.sg) where he runs the Advanced Chalcogenides Technologies and Applications Lab (www.actalab.com). His research interests are focused on designing active materials and applying them to applications in electronics, photonics, and data storage. Prior to joining SUTD Rob received his PhD from the Optoelectronics Research Centre at the University of Southampton, spent three years at the Japanese national institute for Applied Industrial Science and technology (AIST) as a JSPS postdoctoral fellow, and one year as a Marie Curie fellow at the Institut de Ciencies Fotoniques (ICFO), Barcelona. Robert’s research has been awarded a number of prizes including the Westminster medal and the AIST president’s award. He has seven US patents and is the author of many influential papers in Nature Nanotechnology, Nature Materials, Nature Communications, Advanced Materials, Nano Letters, Scientific Reports, and others.