Analytical model and simulation of the Schottky effect on a cryo-cooled bialkali photocathode

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Abstract

A bialkali photocathode with the quantum efficiency (QE) in the range of a few percent was fabricated for the 704 MHz SRF gun at Brookhaven National Laboratory. The photoemission properties of the bialkali photocathode in the superconducting radio frequency (SRF) gun were measured for the first time, and a good beam experiment result was obtained. The performance of the bialkali photocathode was investigated during the commissioning process of the 704 MHz SRF gun. The effect of electric field on the QE of the cryo-cooled cathode was characterized by an analytical model and a code for the first time.

Keywords

Schottky effect Bialkali photocathode Surface potential Superconducting radio frequency gun 

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Copyright information

© Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Chinese Nuclear Society, Science Press China and Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.State Key Laboratory of Nuclear Physics and Technology, Institute of Heavy Ion PhysicsPeking UniversityBeijingChina
  2. 2.Brookhaven National LaboratoryUptonUSA

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