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Updated: Aug 5, 2026

Fabrication and Characterization of Superconducting Resonators
Published on: May 21, 2016
Fabry-Perot resonance cavity for ultra-thin GaAs negative electron affinity photocathodes
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Electron accelerator and photodetector require negative electron affinity photocathode (NEA-PC) with high quantum efficiency (QE), short response time and low mean transverse energy (MTE). Finding a NEA-PC that simultaneously meets all these requirements is challenging. Here, a Fabry-Perot (F-P) cavity with a high reflective silver (Ag) mirror was used for GaAs NEA-PC, which was analyzed by a coupled Monte Carlo opto-electronic model. For the concerned wavelengths of 532 and 780 nm, enhanced light absorption peaks with Q-factor > 20 were obtained in a 100 nm ultra-thin GaAs NEA-PC layer by the standing wave resonance of the F-P cavity, which lead to the enhanced QE higher than that of the normal thick ones, the picoseconds short response time, and the MTE less than 70 meV, respectively. Given these properties, Ag F-P resonant ultra-thin GaAs NEA-PC represent a promising photocathode to provide the high-brightness short-pulse electron beams and high-sensitive fast-response detectors for the electron accelerator and photodetection applications, respectively.
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