For the polarization of neutrons with an energy level of \textcolor{black}{>0.1 eV}, we developed a novel polarized proton spin filter based on dynamic nuclear polarization using photo-excited triplet electron spins. The spin filter consists of a single crystal of naphthalene doped with deuterated pentacene and has a size of ϕ15×4mm3, allowing it to cover a wide beam diameter. It was operated in 0.35 T and at 90 K. We succeeded in polarizing neutrons in the energy range 0.1−10 eV using a RIKEN accelerator-driven compact neutron source. The averaged values of the proton and neutron polarization were 0.250±0.050 and 0.076±0.015, respectively.
@article{arxiv.2004.10370,
title = {Polarized proton spin filter for epithermal neutron based on dynamic nuclear polarization using photo-excited triplet electron spins},
author = {Shusuke Takada and Kenichiro Tateishi and Yasuo Wakabayashi and Yoshimasa Ikeda and Tamaki Yoshioka and Yoshie Otake and Tomohiro Uesaka},
journal= {arXiv preprint arXiv:2004.10370},
year = {2020}
}