In-situ optical pumping for polarizing 3He neutron spin filters at the China Spallation Neutron Source

Zhang, Junpei; Huang, Chenyang; Qin, Zecong; Ye, Fan; Amir, S. M.; Saeed, Ahmed; Dong, Yuchen; Tian, Long; Buck, Zachary Nortis; Kreuzpaintner, Wolfgang; Musgrave, M.; Qi, Xin; Wang, Tianhao; Tong, Xin

doi:10.1007/s11433-021-1876-0

Cited by 9 publications

(3 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This sensitivity represents six orders of magnitude better energy resolution compared to comagnetometers using Rb isotopes that were used to search for exotic gravity coupling to proton spins [17]. The improvement of nuclear spin coherence time and polarization is also beneficial for NMR gyroscopes, noble-gas-spins-based quantum memory, coherent bidirectional coupling between light and noble-gas spins [5], as well as for neutron spin filters [45]. Existing limits and projected sensitivity on the coupling-constant product gSgP of the spin-dependent force between the neutron (proton) spin and unpolarized nucleon.…”

Section: Discussionmentioning

confidence: 99%

Ultrasensitive atomic comagnetometer with enhanced nuclear spin coherence

Wei¹,

Zhang²,

Fang³

et al. 2022

Preprint

View full text Add to dashboard Cite

Achieving high energy resolution in spin systems is important for fundamental physics research and precision measurements, with alkali-noble-gas comagnetometers being among the best available sensors. We found a new relaxation mechanism in such devices, the gradient of the Fermi-contactinteraction field that dominates the relaxation of hyperpolarized nuclear spins. We report on precise control over spin distribution, demonstrating a tenfold increase of nuclear spin hyperpolarization and transverse coherence time with optimal hybrid optical pumping. Operating in the self-compensation regime, our 21 Ne-Rb-K comagnetometer achieves an ultrahigh inertial rotation sensitivity of 3 × 10 −8 rad/s/Hz 1/2 in the frequency range from 0.2 to 1.0 Hz, which is equivalent to the energy resolution of 3.1 × 10 −23 eV/Hz 1/2 . We propose to use this comagnetometer to search for exotic spin-dependent interactions involving proton and neutron spins. The projected sensitivity surpasses the previous experimental and astrophysical limits by more than four orders of magnitude.Coherent control of electron and nuclear spins via lightmatter interactions is an important platform for fundamental physics research [1], and an essential tool for quantum sensors [2-4] and quantum information processing [5]. Dense mixture of vapors of polarized alkali-metal atoms and noble gases with hyperpolarized nuclei have found prominent use in quantum-technology devices such as atomic magnetometers and comagnetometers. Particularly, atomic comagnetometers with hybrid spin ensembles are used to search for "new physics", including fifth forces [6,7], axion-like particles [8,9], permanent electric dipole moments [10,11], and to test thee combined charge-paritytime (CPT) and Lorentz symmetries [12,13].These applications have long been limited by systematic errors and spurious signals due to magnetic field from ambient environment or interactions between atoms [14,15]. A typical approach for addressing this problem is to isolate the magnetic-field effect by using two species with different gyromagnetic ratio, for example, 129 Xe and 131 Xe [8, 16], 3 He and 129 Xe [10, 11], 85 Rb and 87 Rb [17], different nuclear spins in the same molecule [15] or different hyperfine levels of single-species atoms [18]. Another approach is operating the alkali-noble gas atomic comagnetometer in the self-compensation (SC) regime [4,19], where noble gas nuclear spins interact with alkali electron spins by spin-exchange (SE) interactions and adiabatically cancel slowly changing magnetic fields. Another advantage of SC comagnetometer is that the alkali atoms are in the spin-exchange relaxation free (SERF) regime, one can achieve sub-femtotesla magnetic sensitivity [20].

show abstract

Section: Discussionmentioning

confidence: 99%

Ultrasensitive atomic comagnetometer with enhanced nuclear spin coherence

Wei¹,

Zhang²,

Fang³

et al. 2022

Preprint

View full text Add to dashboard Cite

show abstract

“…The majority of the sample stages are made of aluminium alloy and the front of the detector tank is made of stainless steels to avoid the magnetic force of the stray field. Full polarizing scattering is also feasible, although the radio frequency polarizing flipper and the in situ SEOP 3 He polarizing analyser (Huang et al, 2021;Zhang et al, 2022) may be affected by stray field from the 5 T magnet, restricting the maximum magnetic field to less than 2 T.…”

Section: Figurementioning

confidence: 99%

The multi-slit very small angle neutron scattering instrument at the China Spallation Neutron Source

Zuo,

Han,

et al. 2024

J Appl Crystallogr

View full text Add to dashboard Cite

A multi-slit very small angle neutron scattering (MS-VSANS) instrument has been finally accepted at the China Spallation Neutron Source (CSNS). It is the first spallation neutron source based VSANS instrument. MS-VSANS has a good signal-to-noise ratio and can cover a wide scattering vector magnitude range from 0.00028 to 1.4 Å−1. In its primary flight path, a combined curved multichannel beam bender and sections of rotary exchange drums are installed to minimize the background downstream of the instrument. An exchangeable multi-slit beam focusing system is integrated into the primary flight path, enabling access to a minimum scattering vector magnitude of 0.00028 Å−1. MS-VSANS has three modes, namely conventional SANS, polarizing SANS and VSANS modes. In the SANS mode, three motorized high-efficiency 3He tube detectors inside the detector tank cover scattering angles from 0.12 to 35° simultaneously. In the polarizing SANS mode, a double-V cavity provides highly polarized neutrons and a high-efficiency 3He polarization analyser allows full polarization analysis. In the VSANS mode, an innovative high-resolution gas electron multiplier detector covers scattering angles from 0.016 to 0.447°. The absolute scattering intensities of a selection of standard samples are obtained using the direct-beam technique; the effectiveness of this method is verified by testing the standard samples and comparing the results with those from a benchmark instrument. The MS-VSANS instrument is designed to be flexible and versatile and all the design goals have been achieved.

show abstract

“…The first generation in-situ system achieved a stable 3 He polarization of 74.4% . In 2020, its development process and calibration experiment are given in detail in our recent article [18]. The 3 He system is also capable of providing 3 He spin flips with a 3 He polarization loss less than 0.1% per spin-flip (Figure 2(c)), in comparison to ∼ 0.19%/h polarizing pumping rate around saturation, further optimization on laser synchronization and AFP electronic system will be done to reduce the polarization loss, to meet the demands of frequent flipping of the 3 He polarization for most CSNS's beamlines.…”

Section: Seopmentioning

confidence: 99%

Development of polarized neutron techniques at the China Spallation Neutron Source

Tian

Huang

Dong

et al. 2023

J. Phys.: Conf. Ser.

Self Cite

View full text Add to dashboard Cite

In this article, the ongoing development progress of the polarized neutron technique developments at the China Spallation Neutron Source (CSNS) is presented. The general goal of establishing polarized neutron capability in parallel to CSNS beamline construction is also explained. The key instrument development projects of developing the Spin-Exchange Optical Pumping (SEOP) 3He systems, polarized neutron devices, and their application on neutron beamlines are demonstrated. Performance parameters of the developed techniques are also discussed.

show abstract

In-situ optical pumping for polarizing 3He neutron spin filters at the China Spallation Neutron Source

Cited by 9 publications

References 46 publications

Ultrasensitive atomic comagnetometer with enhanced nuclear spin coherence

Ultrasensitive atomic comagnetometer with enhanced nuclear spin coherence

The multi-slit very small angle neutron scattering instrument at the China Spallation Neutron Source

Development of polarized neutron techniques at the China Spallation Neutron Source

Contact Info

Product

Resources

About