Thermal limit to the intrinsic emittance from metal photocathodes

Journal Article · Mon Sep 28 04:00:00 EDT 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4931976· OSTI ID:22482187

Feng, Jun; Nasiatka, J.; Wan, Weishi; Karkare, Siddharth; Padmore, Howard A. ^[1]; Smedley, John ^[2]

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1. Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)
2. Brookhaven National Laboratory, Upton, New York 11973 (United States)

Measurements of the intrinsic emittance and transverse momentum distributions obtained from a metal (antimony thin film) photocathode near and below the photoemission threshold are presented. Measurements show that the intrinsic emittance is limited by the lattice temperature of the cathode as the incident photon energy approaches the photoemission threshold. A theoretical model to calculate the transverse momentum distributions near this photoemission threshold is presented. An excellent match between the experimental measurements and the theoretical calculations is demonstrated. These measurements are relevant to low emittance electron sources for Free Electron Lasers and Ultrafast Electron Diffraction experiments.

• OSTI ID: 22482187
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 13 Vol. 107; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANTIMONY
ELECTRON DIFFRACTION
ELECTRON SOURCES
FREE ELECTRON LASERS
PHOTOCATHODES
PHOTOEMISSION
PHOTONS
THIN FILMS
TRANSVERSE MOMENTUM