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Spin polarized photocathodes are key to the future operation of electron accelerators such as the ones at Thomas Jefferson National Accelerator Facility and Brookhaven National Laboratory. Currently, these photocathodes come in short supply due to limited production by molecular beam epitaxy. By developing a process to implement similar structures using metal organic chemical vapor deposition, the availability of these devices can be increased. In this paper, we detail the implementation of recent photocathode advancements via metal organic chemical vapor deposition process and show an improvement in both polarization and quantum efficiency of our devices compared to those fabricated via molecular beam epitaxy, with devices reaching 82% polarization and 2.9% quantum efficiency. [ABSTRACT FROM AUTHOR]

Techniques for nonevaporable getter (NEG) coating a large diameter chamber are presented along with vacuum measurements in the chamber using several pumping configurations, with base pressure as low as 1.56 × 10−12 Torr (N2 equivalent) with only a NEG coating and a small ion pump. The authors then describe modifications to the NEG coating process to coat complex geometry chambers for ultracold atom trap experiments. Surface analysis of NEG coated samples is used to measure the composition and morphology of the thin films. Finally, pressure measurements are compared for two NEG coated polarized electron source chambers: the 130 kV polarized electron source at Jefferson Lab and the upgraded 350 kV polarized electron source, both of which are approaching or within the extreme high vacuum range, defined as P < 7.5 × 10−13 Torr. [ABSTRACT FROM AUTHOR]