Abstract
Hyperpolarized 3He 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 3He polarization system at the China Mianyang Research Reactor(CMRR),utilizing the metastability-exchange 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 3He atoms and conducted free induction decay(FID)detection of the polarized 3He nuclei using both pickup coil and optical methods.For the optical method,we used a 50 mW linearly polarized distributed Bragg reflector(DBR)laser as the probe.We applied transverse light absorption polarime-try to measure the absolute nuclear polarization of the ground-state 3He.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 3He at a pressure of 100 Pa.Subsequently,we conducted a comprehensive evaluation of their performance in the context of MEOP.
基金项目
National Natural Science Foundation of China(U2230207)
National Natural Science Foundation of China(U2030209)
National Natural Science Foundation of China(12305114)
National Natural Science Foundation of China(12305125)
Sichuan Science and Technology Program(2024NSFSC1356)
National Key Research and Development Program of China(2020YFA0406001)
National Key Research and Development Program of China(2020YFA0406002)
万方数据