MEOP based 3He polarization and injection system for experiments below 1 K

T. Rao; L. Barron-Palos; I. Berkutov; C. Crawford; R. Golub; P. Huffman; M. Konieczny; E. Korobkina; Austin Reid; B. Salazar-Angeles; C. Smith; R. Tat

arXiv · 2411.07197

MEOP based 3He polarization and injection system for experiments below 1 K

T. Rao·L. Barron-Palos·I. Berkutov·C. Crawford·R. Golub·P. Huffman·M. Konieczny·E. Korobkina·Austin Reid·B. Salazar-Angeles·C. Smith·R. Tat

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Abstract

Metastability exchange optical pumping (MEOP) is a widely used technique for producing polarized $^{3}$He. In connection with an experiment to search for the electric dipole moment of the neutron (nEDM) we have built a MEOP based $^{3}$He polarization and injection system to prepare 80 % polarized $^{3}$He at room temperature which will be injected into a ~400 mK measurement cell filled with superfluid $^{4}$He. We describe the polarization and injection system, which is designed to allow for final concentrations of $10^{-8}-10^{-10}$ of 80 % polarized $^{3}$He in the superfluid filled measurement cell. Only $\approx0.72\%$ polarization loss due to gradients is expected during injection

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T. Rao, L. Barron-Palos, I. Berkutov, C. Crawford, R. Golub, P. Huffman, M. Konieczny, E. Korobkina, Austin Reid, B. Salazar-Angeles, C. Smith, R. Tat. 2024-11-11. MEOP based 3He polarization and injection system for experiments below 1 K. https://arxiv.org/abs/2411.07197

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