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arXiv · 2205.03693

New spin-polarized electron source based on alkali-antimonide photocathode

Abstract

New spin-dependent photoemission properties of alkali antimonide semiconductor cathodes are predicted based on the detected optical spin orientation effect and DFT band structure calculations. Using these results, the Na$_2$KSb/Cs$_3$Sb heterostructure is designed as a spin-polarized electron source in combination with the Al$_{0.11}$Ga$_{0.89}$As target as a spin-detector with spatial resolution. In the Na$_2$KSb/Cs$_3$Sb photocathode, spin-dependent photoemission properties were established through detection of high degree of photoluminescence polarization and high polarization of the photoemitted electrons. It was found that the multi-alkali photocathode can provide electron beams with emittance very close to the limits imposed by the electron thermal energy. The vacuum tablet-type sources of spin-polarized electrons have been proposed for accelerators, that can exclude the construction of the photocathode growth chambers for photoinjectors.

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V. S. Rusetsky, V. A. Golyashov, S. V. Eremeev, D. A. Kustov, I. P. Rusinov, T. S. Shamirzaev, A. V. Mironov, A. Yu. Demin, O. E. Tereshchenko. 2022-05-07. New spin-polarized electron source based on alkali-antimonide photocathode. https://doi.org/10.1103/physrevlett.129.166802

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