This research involves the characterization of electron emitter materials for photoemission, secondary emission, and field emission applications. The studies focus on probing the chemistry and electronic structure at the surfaces of various emitter materials and on characterizing the emission generated through different excitation mechanisms (e.g., electron or photo impact, field-enhanced tunneling). Materials of interest include wide bandgap semiconductors (diamond, GaN), Cs-based compounds, and carbon nanotubes. Experimental studies will be used to identify the mechanisms that govern the emission process at various surfaces and structures, and this understanding will be applied to optimize the emission performance. The facilities include a photoelectron emission microscope and a range of electron analytical techniques (Auger electron spectroscopy, secondary electron emission spectroscopy, x-ray photoelectron spectroscopy, and low-energy electron diffraction) that are used to measure the intensity, energy distribution, and spatial uniformity of the emitted electrons.

 

Keywords:

Diamond; Electron emitter materials; Field emission; PEEM; Photoemission; Secondary emission; Semiconductors; Surface science; UHV;

Citizenship:  Open to U.S. citizens and permanent residents

Level:  Open to Postdoctoral applicants