Spin pump for boosting spin polarization of superfluidHe3A1phase

Abstract

Mechanical pumping and filtering of spin-polarized condensate were realized in the superfluid 3 He A 1 phase by the pneumatic pumping action of an electrostatically actuated diaphragm. Spin pumping increased the net spin polarization by 20-50 % as measured by the induced pressure change during spin pumping. The observed spin relaxation time was consistent with the increased spin polarization. These observations demonstrate the feasibility of using spin pumping to substantially increase the effective magnetic field to which the A 1 phase is exposed.

Spin fluid dynamics observed by magnetic fountain effect and mechanical spin pumping effect in the ferromagnetic superfluidH3eA1Aoki1, Yamaguchi2, Suzuki3 et al. 2010Phys. Rev. BSelf Cite3000View full textAdd to dashboardCite

“…As stated earlier, the MSE has an advantage over the MFE in that there is no issue with the critical current in the gradient field coils under high static magnetic fields. In a separate MSE device specifically designed to boost spin polarization, changes in polarization greater than those observed here by four orders of magnitude have been achieved [12].…”

“…While the values of τ measured using the MFE method continues to increase up to 8 T, those measured using the MSE method saturate in the range µ 0 H 6 T. Clearly, more work is needed in the high field range. Understanding of the entire field dependence of τ is important to boosting the spin polarization achievable using spin pumping techniques [12].…”

“…The most important among these questions is the origin of the unexpected spin relaxation observed in MFE experiments. Understanding this spin relaxation would yield important clues in designing a spin pumping device for boosting the spin polarization to much greater level than feasible by available static magnetic fields [12]. In this report, we describe our recent experiments on both magnetically and mechanically driven spin superflows in the superfluid 3 He A 1 phase.…”