Pellin Plasmonic Photocathodes Cherenkov Radiation Photocathode h -> e- β = v p / c 1.Ag Particles...

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Pellin Plasmonic Photocathodes Cherenkov Radiation Photocathode hu-> e- β = v p / c 1. Ag Particles 2. Ag Arrays 3. Ag Films

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Plasmonic Photocathodes

PellinPlasmonic Photocathodes

Cherenkov Radiation

Photocathodehu-> e- = vp / cAg ParticlesAg ArraysAg FilmsThe Problem With Photocathodes Photon Absorption Length vs Electron escape depthKey Factors in optimizing Cathode EfficiencyWindow should be transparentPhotocathode should absorb and produce an electron in the solidElectron should be close to the surfaceSurface work function should allow the excited electron to escape (but not all the rest of the electrons.

2WindowFilled StatesEmpty StateshNo States

1 monolayer dyePlasmon What is it?In a conductor, the free electrons move around the fixed ionic cores to cancel externally applied fields.Oscillatory fields like light waves have resonance conditions. These conditions dominate the absorption properties of good metals.The proper resonance conditions depend of particle size or surface features. For visible light this is