Events in Physics
Dr. Phil King (St. Andrews)
An ARPES view of topological insulator surfaces
Topological insulators (TIs) are a recently discovered form of quantum matter characterized by a bulk band inversion driven by strong spin-orbit coupling. They maintain a band gap in the bulk, but unusually possess unconventional surface states which are guaranteed to be metallic. Angle-resolved photoemission (ARPES) is an ideal tool to study the detailed electronic structure of these surface Dirac fermions. I will present our recent ARPES measurements of the Bi-chalcogenide family of TIs. While several of these compounds suffer from degenerate n-type self-doping, we show that Te-rich ternary compounds can have an insulating bulk. Thus, these are model examples of true topological insulators, where only a single topological surface state intersects the chemical potential. By adsorbing n-type dopants at the surface of several TIs, we mimic the effects of an externally-applied gate voltage, of the form desirable for electronic applications. We create a two-dimensional electron gas (2DEG) that co-exists with the topological surface state and can be driven to develop a large Rashba spin-splitting, suggesting potential for its application in advanced spintronic devices such as the spin-transistor. The tuneable surface band bending also provides a novel opportunity to probe the interplay of quantization and topological order.
Academic Leave Diary
Physics Days
Research Group Events
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Open Funder Deadlines
UKRI - Daphne Jackson Fellowship
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UKRI Deadlines
Due to the implementation of a new UKRI funding system (TFS) there will be a fixed quarterly deadlines for some grants which would previously have been on open calls, this is to allow necessary system amendments and updates.
The first deadline after implementation will be 28th September 2023 and applies to those calls listed below:
EPSRC Post Doctoral Fellowship
EPSRC Working with overseas scientists