We demonstrate the use of spatial emission patterns to measure magnetic fields. The directional aspect of the Hanle effect gives a direct, visual presentation of the magnetic fields, in which brighter fluorescence indicates larger fields. It can be used to determine the direction as well as the magnitude of the field. It is particularly well suited for characterizing and aligning magneto-optical traps, requiring little or no additional equipment or setup beyond what is ordinarily used in a magneto-optical trap, and being most sensitive to fields of the size typically present in a magneto-optical trap.
A hybrid Zeeman slower for lithium
Zeeman slowers come in two commonly used types: electromagnet-based slowers and permanent-magnet slowers. Both have characteristic advantages and disadvantages. The electric currents required to create strong magnetic fields lead to heat dissipation that limits the achievable fields, while permanent-magnet slowers cause bias magnetic fields at the position of the magneto-optical trap. Here, we combine both approaches and their advantages at our lithium-6 triangular-lattice quantum gas microscope and extend the field of an electromagnet-based Zeeman slower using permanent magnets. We observe nearly doubled loading rates of the magneto-optical trap and no significant stray fields in the trapping region. Our approach allows for a stronger magnetic field in places where geometric constraints prevent the use of coils, and it provides a low-cost upgrade to the loading rate at established experiments.
more » « less- Award ID(s):
- 2047275
- PAR ID:
- 10363725
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Review of Scientific Instruments
- Volume:
- 93
- Issue:
- 3
- ISSN:
- 0034-6748
- Page Range / eLocation ID:
- Article No. 033202
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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We demonstrate a simple and compact variable magnetic field source based on the permanent cube magnet array approximating a Halbach cylinder. The large air gap area accommodates standard cryostat tails while providing a high uniformity and magnetic field stability of up to 0.5 T over regions of up to about a centimeter. It eliminates magnetic remanence effects and produces reproducible fields without the need for feedback. Thanks to the low cost and exceptional energy efficiency, it provides an accessible solution for modest magnetic field requirements in a wide range of research applications.
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