Dr. Christopher Edgcombe

Dr. Edgcombe has pursued many apparently different topics within the general field of electron (wave) optics. His PhD work at Cambridge studied the generation of microwaves with a spiralling electron beam. At EEV Ltd (now E2V) he developed high-power amplifiers for UHF TV broadcasting and software for electron beam design. In further work with EEV at Cambridge, he developed a gyrotron for fusion power applications. Moving to the Department of Physics at Cambridge, he created a method for microwave measurement of high-Tc superconductors, and joined the electron microscopy group of Archie Howie and Mick Brown, working on theory of field emitters and on phase plates for transmission microscopes. His current interests include developments in transmission microscopy to improve biomedical imaging.

Tentative Title: Field emitters at atomic scale – insights from density functional calculations

Website: https://www.magd.cam.ac.uk/user/edgcombe

Abstract: The apex region of a capped (5,5) carbon nanotube (CNT) has been modelled by density functional theory using adaptive basis functions. These determine individual Kohn-Sham orbitals and other properties of the CNT, and allow their variation with applied field to be investigated. Some implications for the macroscopic modelling of field emitters will be discussed.