Short pulse photoemission from LaB6-based materials

Development of a UHV-compatible Low-energy Electron Gun using the Photoelectric Effect

“…where I PE is the emitted photoelectron current, P the light source power, E ph the incident photon energy, and e the elementary electric charge. Table 1 lists h measured at cathode temperatures of 300 and 800 K under light source condition of E ph ＝2.62 eV and P＝0.1 W together with the results of Leblond et al 2) The quantum e‹ciency is known to be proportional to (E ph -q) 2 at the weak electricˆeld limit 4) . The results listed in Table 1 roughly follow this relation.…”

“…5. Here, f(E) is given as Table 1 Measured quantum e‹ciency h of the electron gun together with the results of Leblond et al 2) .…”

“…Leblond et al 2) 3.49 eV 2.4×10 -4 4.66 eV 6.8×10 -4 where E, e f , k B and T are the electron energy level, the Fermi level of the cathode, the Boltzmann constant, and the temperature of the cathode, respectively. A photon of energy E ph can emit an electron occupying an energy level higher than E min ＝E vac -E ph ＝e f ＋q-E ph .…”

“…Over the past three decades, electron sources using the photoelectric eŠect 1,2) have been developed and widely used in accelerators. These photoelectron guns can generate electron beams with large current, low emittance, and narrow time pulses 1) .…”

Infrared photoelectron emission from Scandate dispenser cathodes

“…Previously reported multiphoton emission experiments [6][7][8][9][10][11][12][13] have been on metals with work functions of 4 -5 eV and with shorter laser pulse lengths ͑generally 100-450 fs or smaller͒. In most of these studies, the incident photons had energies greater than the work functions of the target metals.…”