Fabrication and rejuvenation of high quantum efficiency caesium telluride photocathodes for high brightness and high average current photoinjectors

Bibliographic Details
Title: Fabrication and rejuvenation of high quantum efficiency caesium telluride photocathodes for high brightness and high average current photoinjectors
Authors: M. Martinez-Calderon, E. Chevallay, R. E. Rossel, L. B. Jones, G. Zevi Della Porta, B. Marsh, E. Granados
Source: Physical Review Accelerators and Beams, Vol 27, Iss 2, p 023401 (2024)
Publisher Information: American Physical Society, 2024.
Publication Year: 2024
Collection: LCC:Nuclear and particle physics. Atomic energy. Radioactivity
Subject Terms: Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
More Details: With their high quantum efficiency (QE) and excellent photoemissive properties, cesium telluride (Cs-Te) photocathodes are the current workhorse in the high average current electron accelerators around the globe. Their ability to generate high brightness and high charge electron beams has opened the doorway to numerous applications, including fundamental particle physics research, radiation therapy, high-energy physics experiments, and high repetition rate free-electron lasers (FELs). Their long-term performance is critical. In this work, we analyze the systematic production and rejuvenation of photocathodes via thermal evaporation and deposition techniques (both sequential and co-deposition), showing excellent values of QE exceeding 20% using deep ultraviolet illumination (λ=262–266 nm). To extend the photocathode lifetime, the rejuvenation process is performed via multilayer thin-film co-deposition, demonstrating the feasibility of reliably recovering the initial QE even after air exposure. We evaluated their final performance in both high gradient dc and rf gun setups and obtained consistent results of QE and lifetimes. The technique can be used in situ at the gun level, which significantly extends the sustained accelerator operation without major interventions. These approaches significantly enhance the robustness and performance of Cs-Te photoinjectors and represent a significant advancement for reliable high average current electron accelerators and FELs.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2469-9888
Relation: https://doaj.org/toc/2469-9888
DOI: 10.1103/PhysRevAccelBeams.27.023401
Access URL: https://doaj.org/article/3770902331a94eb59e58c97b06b82caf
Accession Number: edsdoj.3770902331a94eb59e58c97b06b82caf
Database: Directory of Open Access Journals
More Details
ISSN:24699888
DOI:10.1103/PhysRevAccelBeams.27.023401
Published in:Physical Review Accelerators and Beams
Language:English