Active stabilization of kilogauss magnetic fields to the ppm level for magnetoassociation on ultranarrow Feshbach resonances

Mateusz Borkowski; Lukas Reichsöllner; Premjith Thekkeppatt; Vincent Barbé; Tijs van Roon; Klaasjan van Druten; Florian Schreck

doi:10.1063/5.0143825

Active stabilization of kilogauss magnetic fields to the ppm level for magnetoassociation on ultranarrow Feshbach resonances

Rev Sci Instrum. 2023 Jul 1;94(7):073202. doi: 10.1063/5.0143825.

Authors

Mateusz Borkowski^{1

2

3}, Lukas Reichsöllner¹, Premjith Thekkeppatt¹, Vincent Barbé¹, Tijs van Roon⁴, Klaasjan van Druten¹, Florian Schreck¹

Affiliations

¹ Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
² Department of Physics, Columbia University, 538 West 120th Street, New York, New York 10027-5255, USA.
³ Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziądzka 5, 87-100 Toruń, Poland.
⁴ Technology Center, Faculty of Science, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.

PMID: 37409908
DOI: 10.1063/5.0143825

Abstract

Feshbach association of ultracold molecules using narrow resonances requires exquisite control of the applied magnetic field. Here, we present a magnetic field control system to deliver magnetic fields of over 1000 G with ppm-level precision integrated into an ultracold-atom experimental setup. We combine a battery-powered, current-stabilized power supply with active feedback stabilization of the magnetic field using fluxgate magnetic field sensors. As a real-world test, we perform microwave spectroscopy of ultracold Rb atoms and demonstrate an upper limit on our magnetic field stability of 2.4(3) mG at 1050 G [2.3(3) ppm relative] as determined from the spectral feature.

MeSH terms

Electric Power Supplies*
Magnetic Fields*
Vibration