A polarized^(3)He system based on metastability-exchange optical pumping  

作　　者：Yuting Wang Liangyong Wu Kaiyuan Zhang Mei Peng Siyu Chen Haiyang Yan 

机构地区：[1]State Key Laboratory of Nuclear Physics and Technology,School of Physics,Peking University,Beijing 100871,China [2]Institute of Nuclear Physics and Chemistry,China Academy of Engineering Physics,Mianyang 621900,China [3]Key Laboratory of Nuclear Physics and Ion-beam Application(MOE),Fudan University,Shanghai 200433,China [4]Key Laboratory of Neutron Physics,Institute of Nuclear Physics and Chemistry,China Academy of Engineering Physics,Mianyang 621900,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2024年第7期72-81,共10页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.U2230207,U2030209,12305114,and 12305125);Sichuan Science and Technology Program(Grant No.2024NSFSC1356);the National Key Research and Development Program of China(Grant Nos.2020YFA0406001,and 2020YFA0406002)。

摘　　要：Hyperpolarized^(3)He nuclei have emerged as a significantly important approach in quantum precision measurement techniques,with extensive applications in fundamental physics,magnetometry,metrology,and beyond.In this study,we report on the design and implementation of a^(3)He polarization system at the China Mianyang Research Reactor(CMRR),utilizing the metastabilityexchange optical pumping(MEOP)method.We employed a Merritt coil system consisting of four square coils to furnish a uniform holding field.We deployed a 2 W fiber laser to pump the metastable^(3)He atoms and conducted free induction decay(FID)detection of the polarized^(3)He nuclei using both pickup coil and optical methods.For the optical method,we used a50 m W linearly polarized distributed Bragg reflector(DBR)laser as the probe.We applied transverse light absorption polarimetry to measure the absolute nuclear polarization of the ground-state^(3)He.We have developed cell fabrication capabilities at the CMRR,and cells at various pressures ranging from 100 to 1000 Pa have been fabricated and evaluated.For a typical borosilicate cell with 100 Pa pressure,the absolute polarization is measured as Pn≈70%,and the transverse relaxation time is estimated as T2≈0.5 s.Moreover,we constructed a few aluminosilicate cells,each carefully filled with pure^(3)He at a pressure of 100 Pa.Subsequently,we conducted a comprehensive evaluation of their performance in the context of MEOP.

关 键 词：metastability exchange optical pumping polarized^(3)He magnetic resonance 

分 类 号：O482.53[理学—固体物理]