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DOE OSTI · 3018633

Towards advanced polarized electron sources

Litvinenko, Vladimir N. [Stony Brook Univ., NY (United States)] (ORCID:0000000224186060)·Bachhawat, Nikhil [Stony Brook Univ., NY (United States)] (ORCID:0000000191020127)·Brutus, Jean Clifford [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0009000005333574)·Cultrera, Luca [Brookhaven National Laboratory (BNL), Upton, NY (United States)]·Decker, Kenneth [Brookhaven National Laboratory (BNL), Upton, NY (United States)]·Gaowei, Mengjia [Brookhaven National Laboratory (BNL), Upton, NY (United States)]·Inacker, Patrick [Brookhaven National Laboratory (BNL), Upton, NY (United States)]·Jing, Yichao [Brookhaven National Laboratory (BNL), Upton, NY (United States)]·Ma, Jun [Brookhaven National Laboratory (BNL), Upton, NY (United States)]·Mondal, Kali Prasanna [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000162509126)·Narayan, Geetha [Brookhaven National Laboratory (BNL), Upton, NY (United States)]·Pinayev, Igor [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:000000023718876X)·Severino, Freddy [Brookhaven National Laboratory (BNL), Upton, NY (United States)]·Shih, Kai [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000156454245)·Skaritka, John [Brookhaven National Laboratory (BNL), Upton, NY (United States)]·Smart, Loralie [Brookhaven National Laboratory (BNL), Upton, NY (United States)]·Than, Yatming [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000180716292)·Walsh, John [Brookhaven National Laboratory (BNL), Upton, NY (United States)]·Wang, Erdong [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000199093099)·Wang, Gang [Brookhaven National Laboratory (BNL), Upton, NY (United States)]·Weiss, Dan [Brookhaven National Laboratory (BNL), Upton, NY (United States)]
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Abstract

Polarized electrons play an important role in high-energy and nuclear physics, and their properties have also been exploited in ultrafast electron microscopy. Currently, gallium arsenide crystals illuminated by circular polarized infrared laser light are commonly used for generating polarized electrons. However, the achievable accelerating voltage and the gradient of these electrostatic sources limit the beam quality and quantity. A solution could be to combine gallium arsenide photocathodes with radio-frequency electron guns, which are capable of accelerating beams with significantly higher gradients and voltage. Here we report the successful operation of a gallium arsenide photocathode in a superconducting radio-frequency gun. Our findings are relevant for future sources of polarized electrons.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS

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BibTeXRIS

Litvinenko, Vladimir N. [Stony Brook Univ., NY (United States)] (ORCID:0000000224186060), Bachhawat, Nikhil [Stony Brook Univ., NY (United States)] (ORCID:0000000191020127), Brutus, Jean Clifford [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0009000005333574), Cultrera, Luca [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Decker, Kenneth [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Gaowei, Mengjia [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Inacker, Patrick [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Jing, Yichao [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Ma, Jun [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Mondal, Kali Prasanna [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000162509126), Narayan, Geetha [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Pinayev, Igor [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:000000023718876X), Severino, Freddy [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Shih, Kai [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000156454245), Skaritka, John [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Smart, Loralie [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Than, Yatming [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000180716292), Walsh, John [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Wang, Erdong [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000199093099), Wang, Gang [Brookhaven National Laboratory (BNL), Upton, NY (United States)], Weiss, Dan [Brookhaven National Laboratory (BNL), Upton, NY (United States)]. 2026-02-02. Towards advanced polarized electron sources. https://doi.org/10.1038/s41567-025-03138-7

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