Colum’s research focuses on the development and applications of phase-imaging techniques in scanning transmission electron microscopy (STEM). He is particularly interested in focused-probe electron ptychography: an imaging technique capable of visualising light elements and radiation-sensitive materials on the atomic scale. However, the implementation of electron ptychography for imaging such materials currently faces several challenges.
Firstly, the cameras used to collect the data are 100 times slower than the detectors used for conventional STEM imaging modes. To overcome this issue, Colum and others have used binary data acquisition to increase camera readout speeds by a factor of 10. Faster detector speeds allow data acquisition to be performed using much lower electron intensities, enabling imaging of beam sensitive materials such as zeolites, polymers and energy materials.
Another challenge of imaging radiation-sensitive materials using ptychography is the efficiency of the imaging method. Colum has been studying the contrast transfer mechanisms and noise considerations of electron ptychography to better understand how ptychographic techniques can be applied to noisy data sets.
Colum is a final year DPhil Candidate in Materials, originally from Dublin, Ireland. He completed his bachelor's degree in Physics at Trinity College Dublin, after which he moved to Oxford to pursue his graduate studies. Outside of the lab, Colum enjoys playing Gaelic football, running in muddy fields and telling poor-quality jokes.
30.15 Holder Building
Department of Materials, University of Oxford
Parks Road, Oxford, OX1 3PH
Telephone: 01865 273661
Fax: 01865 273789
Email address: colum.oleary@materials.ox.ac.uk
