Cameron, G.; Cuevas, J.; Pound, J., Jr.; Shiner, D. A Miniature Permanent Magnet Assembly with Localized and Uniform Field with an Application to Optical Pumping of Helium. Appl. Sci.2021, 11, 8886.
Cameron, G.; Cuevas, J.; Pound, J., Jr.; Shiner, D. A Miniature Permanent Magnet Assembly with Localized and Uniform Field with an Application to Optical Pumping of Helium. Appl. Sci. 2021, 11, 8886.
Cameron, G.; Cuevas, J.; Pound, J., Jr.; Shiner, D. A Miniature Permanent Magnet Assembly with Localized and Uniform Field with an Application to Optical Pumping of Helium. Appl. Sci.2021, 11, 8886.
Cameron, G.; Cuevas, J.; Pound, J., Jr.; Shiner, D. A Miniature Permanent Magnet Assembly with Localized and Uniform Field with an Application to Optical Pumping of Helium. Appl. Sci. 2021, 11, 8886.
Abstract
Atomic state preparation can benefit from a compact and uniform magnetic field source. Simulations and experimental measurements have been used to design, build, and test such a source as shown by optical pumping of atomic Helium. This source is a 9.5 mm (3/8") OD x 6.7 mm (1/4") ID x 9.5 mm (3/8") long, NdFeB-N42 assembly of 1.6 mm (1/16") thick customized annular magnets. It has octopole decay with a residual dipole far field from imperfect dipole cancelations. It has greater than 50% clear aperture with uniform and collimated magnetic field consistent with the prediction of several models. Octopole roll-off localizes the field minimizing the need for shielding in applications. The device is applied to a high precision 3,4He laser spectroscopy experiment using σ+ or σ- optical pumping currently resulting in a measured 99.3% preparation efficiency and in accordance with a rate-equation model.
Keywords
optical pumping; annular permanent magnet; miniature magnet; laser orbital angular mo-mentum; collimated magnetic field; fringe magnetic field
Subject
Physical Sciences, Atomic and Molecular Physics
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
