Optical and Quantum Sensing and Precision Metrology II

Measuring AC Zeeman shifts using a trapped cold atom interferometer on chip

B. Wirtschafter, Soizic Hello, Christoph Ira Westbrook, Matthieu Dupont-Nivet

Published Mar 19, 2025• 0 citations

Abstract

Atom chip based interferometry holds signicant promise for embedded precise measurements of time, accelerations, rotations, and magnetic fields. It can enable compact sensors for various carriers like planes, boats, and drones, making it advantageous for navigation applications. When measuring acceleration with a cold atom interferometer, it is necessary to separate the two states during the interferometry sequence. Microwave dressed potentials generated from CPWs within a magnetic trap are one approach to achieve such on-chip manipulation. Two specic challenges arise in this process. First, the microwave field emitted by a waveguide introduces an AC Zeeman shifts, leading to a bias phase in the interferometer output. Precise determination of this bias is necessary for accurate parameter readout. Second, positioning the atom trap accurately between the two waveguides is crucial to obtain the necessary symmetry during separation; otherwise, the contrast of the interferometer is signicantly reduced. To address these challenges, we present a method for measuring AC Zeeman shifts using Ramsey interferometry.

DOI: 10.1117/12.3039019

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