Beam (structure)

Engineering

Lepton

Nuclear physics

Atomic physics

Bunches

Radio frequency

Brightness

Monochromatic color

Laser

Continuous wave

Physics

Optics

Superconductivity

Condensed matter physics

Electron gun

Cathode ray

Electron

Electrical engineering

Photocathode

Physical Review Letters

Continuous-wave photoinjectors operating at high accelerating gradients promise to revolutionize many areas of science and applications. They can establish the basis for a new generation of monochromatic x-ray free electron lasers, high-brightness hadron beams, or a new generation of microchip production. In this Letter we report on the record-performing superconducting rf electron gun with ${\mathrm{CsK}}_{2}\mathrm{Sb}$ photocathode. The gun is generating high charge electron bunches (up to $10\text{ }\text{ }\mathrm{nC}/\text{bunch}$) and low transverse emittances, while operating for months with a single photocathode. This achievement opens a new era in generating high-power beams with a very high average brightness.

High-Brightness Continuous-Wave Electron Beams from Superconducting Radio-Frequency Photoemission Gun