NAPAC2022 - List of Authors (Montgomery, E.J.)

Paper	Title	Page
TUYD5	Epitaxial Alkali-Antimonide Photocathodes on Lattice-matched Substrates	289
	P. Saha, S.S. Karkare Arizona State University, Tempe, USA E. Echeverria, A. Galdi, J.M. Maxson, C.A. Pennington Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA E.J. Montgomery, S. Poddar Euclid Beamlabs, Bolingbrook, USA
	Alkali-antimonides photocathodes, characterized by high quantum efficiency (QE) and low mean transverse energy (MTE) in the visible range of spectrum, are excellent candidates for electron sources to drive X-ray Free Electron Lasers (XFEL) and Ultrafast Electron Diffraction (UED). A key figure of merit for these applications is the electron beam brightness, which is inversely proportional to MTE. MTE can be limited by nanoscale surface roughness. Recently, we have demonstrated physically and chemically smooth Cs₃Sb cathodes on Strontium Titanate (STO) substrates grown via co-deposition technique. Such flat cathodes could result from a more ordered growth. In this paper, we present RHEED data of co-deposited Cs₃Sb cathodes on STO. Efforts to achieve epitaxial growth of Cs₃Sb on STO are then demonstrated via RHEED. We find that films grown epitaxially on substrates like STO and SiC (previously used to achieve single crystalline Cs₃Sb) exhibit QE higher than the polycrystalline Cs₃Sb cathodes, by an order of magnitude below photoemission threshold. Given the larger QE, lower laser fluence could be used to extract high charge densities, thereby leading to enhanced beam brightness.
	Slides TUYD5 [2.088 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUYD5
About •	Received ※ 01 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 07 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Epitaxial Alkali-Antimonide Photocathodes on Lattice-matched Substrates

289

P. Saha, S.S. Karkare
Arizona State University, Tempe, USA
E. Echeverria, A. Galdi, J.M. Maxson, C.A. Pennington
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
E.J. Montgomery, S. Poddar
Euclid Beamlabs, Bolingbrook, USA

Alkali-antimonides photocathodes, characterized by high quantum efficiency (QE) and low mean transverse energy (MTE) in the visible range of spectrum, are excellent candidates for electron sources to drive X-ray Free Electron Lasers (XFEL) and Ultrafast Electron Diffraction (UED). A key figure of merit for these applications is the electron beam brightness, which is inversely proportional to MTE. MTE can be limited by nanoscale surface roughness. Recently, we have demonstrated physically and chemically smooth Cs₃Sb cathodes on Strontium Titanate (STO) substrates grown via co-deposition technique. Such flat cathodes could result from a more ordered growth. In this paper, we present RHEED data of co-deposited Cs₃Sb cathodes on STO. Efforts to achieve epitaxial growth of Cs₃Sb on STO are then demonstrated via RHEED. We find that films grown epitaxially on substrates like STO and SiC (previously used to achieve single crystalline Cs₃Sb) exhibit QE higher than the polycrystalline Cs₃Sb cathodes, by an order of magnitude below photoemission threshold. Given the larger QE, lower laser fluence could be used to extract high charge densities, thereby leading to enhanced beam brightness.

Slides TUYD5 [2.088 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUYD5

About •

Received ※ 01 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 07 September 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)