Seminar: Development of Electron Sources for MeV Transmission Electron Microscope

Date:18-11-2019   |   【Print】 【close

Title: Development of electron sources for MeV Transmission Electron Microscope  

Speaker: Dr. Chunguang Jing (EUCLID) 

Time: 09:00am, Nov.20 (Wednesday), 2019 

Place: Room911, Building 5 


Until recently, in the operation of transmission electron microscopy (TEM), the gold standard high spatial resolution technique has been largely ruled out as a viable time-resolved technique. This is because dynamic events could not be temporally resolved, with the signals time-averaged over milliseconds at best. If the TEM had the additional capability to collect images at high sampling rates with fs/ps/ns resolution, the physics of far-from-equilibrium states and processes could be explored. Benefiting from the rapid progress on RF photocathode gun technologies in the past two decades, the development of MeV-range ultrafast electron diffraction/microscopy (UED and UEM) has been identified as an enabling instrumentation, which may lead to breakthroughs in  fundamental science and applied technologies. 

In order to achieve sharp, high resolution real-time imaging, electrons in a UEM beamline need to minimize instabilities in the magnetic lenses and energy spread during generation and acceleration. Instabilities (timing jitter and energy spread) in UEM introduce a focal spread, thus causing chromatic aberration. In this talk, the speaker will discuss both normal conducting and superconducting photogun that have been developed and developing at Euclid for MeV UEM/UED applications. 

About the speaker:

Chunguang Jing received his PhD in Electrical Engineering in 2005 at the Illinois Institute of Technology. Since graduation he has been a Senior Researcher at Euclid Techlabs LLC, and was promoted to VP for Engineering in 2012. His research interests are focused on high gradient accelerating structures and electron sources. In particular he works on RF coupling design schemes, wakefield acceleration, photoinjectors, field emission sources, breakdown studies and power extraction, etc; all in the range from few GHz to few THz. He has been a Principal Investigator on numbers of US Government Contracts. He has authored and co-authored two book chapters, over 40 refereed journal papers (including RMP, PRL, APL, etc.) and over 200 conference papers. He holds 6 US patents.