Performance of a CsBr coated Nb photocathode at room temperature

Experiments performed on Nb substrates coated with thin films of CsBr indicate a substantial enhancement of 150 to 800 times of the photoyield at 257 nm relative to the uncoated substrates. Results are presented for several power density illuminations and sample thickness. Further enhancement of photoyield was observed when the laser illumination was interrupted for a short time in samples with 5–10 nm thick CsBr coatings.