GaAs Transmission Photocathode Grown by MBE

Negative-electron-affinity (NEA) GaAs/GaP photocathodes have been grown by MBE for the first time. The surfaces of GaAs emitters are atomically smooth. The compositionally graded interface layer GaAsP produced by infer-diffusion at the GaAs/GaP interface has played an important role for a high photoemissive quantum yield and for the spectral response curves of photoemission from the thin GaAs layers.