Minimum intrinsic emittance of photocathodes
Electron beams for X-ray lasers and electron microscopes start when light knocks electrons out of a surface, and the sideways jitter of those electrons sets how sharp the beam can ever be. How small this jitter can be made is unknown.
Why it matters
Intrinsic emittance sets the brightness of photoinjectors and thus the reach of X-ray FELs and ultrafast electron diffraction.
Review
D. H. Dowell, J. F. Schmerge, Quantum efficiency and thermal emittance of metal photocathodes, Physical Review Special Topics - Accelerators and Beams, 2009. https://doi.org/10.1103/PhysRevSTAB.12.074201 reference checked
See also
- Special case of Brightness limits of electron sources and storage rings
Timestamp record
- Signed record
- 3bfc449fad2e…
- Public log
- Entry 71, in checkpoint 2,123
- In the log by
- Block 969,698, 2026-10-03
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