FISHER1	Density functional theory of magnetic atoms and molecules in the STM
Type	Theoretical
#students	1
Orientation	Why is the scientific problem of interest at all? We have many ways of measuring the spin of large ensembles of atoms. However it is much more difficult to learn anything about individual spins localised on single atoms or molecules. One promising route to this is through scanning tunnelling microscopy, where electrons flow between a sharp tip and a sample through an individual atom. In this situation flips of the electron spin can be reflected in the electron current. This project will study the links between those spin flips and the environment of the atom on the surface.
How	How is the research going to shed light on the given problem?. Theoretical modelling of the interactions of magnetic atomic or molecular species on surfaces imaged using scanning tunnelling microscopy Density functional theory (DFT), although imperfect in its current implementations, is the most effective tool we possess to analyse the electronic states in complex systems. It works by reducing the problem of many interacting electrons to one where the electrons instead interact individually with an effective external potential. This makes the problem computationally tractable even for moderately complex systems.
What	What is the specific thing that the student will do, and how does it fit inside the overall project? In this project the student will carry out DFT calculations of transition metal atoms on surfaces, extract from the results parameters that describe the interaction of the spin-bearing (unpaired) electrons with their surroundings,
Special Knowlegde	A good knowledge of, and interest in, quantum mechanics would be a significant advantage.
Supervisor	Prof. Andrew Fisher andrew.fisher@ucl.ac.uk Dr Cyrus Hirjibehedin (2^nd supervisor)