WINDOWS AND PHOTOCATHODES FOR A HIGH-RESOLUTION SOLID-STATE BANDPASS ULTRAVIOLET PHOTON DETECTOR FOR INVERSE-PHOTOEMISSION

We have measured the absolute quantum yield for alkali halides and the spectral transmission for alkaline earth fluoride windows to find an optimized bandpass combination for a solid state ultraviolet (UV) phot on detector for inverse photoemission. The best resolution achieved is 0.33 eV (full width at half-maximum), being obtained with the NaCl ph otocathode-BaF2 window combination. This, however, leads to a rather l ow quantum efficiency of 0.3%. The combination NaCl-SrF2 chosen for ou r detector offers a resolution of 0.42 eV (full width at half-maximum) with a maximum quantum efficiency of 2.5% at 9.50 eV photon energy. ( C) 1997 American Institute of Physics.