Inverse problem approach to evaluate quadratic Zeeman effect for an atomic fountain frequency standard KRISS-F1

Abstract

The evaluation of the quadratic Zeeman shift in atomic fountain frequency standards requires information on the magnetic field distribution along the drift region. Plotting Zeeman frequencies against various launching heights provides the temporally averaged magnetic field values seen by the flying atoms. Using those data, we were able to deduce a reasonable field map by taking the approach of solving an inverse problem. We employed a regularization method after establishing a linear set of equations. The analysis enabled us to evaluate the quadratic Zeeman shift and its uncertainty against various launching heights. Our method encompasses and generalizes the deconvolution method. This paper covers the mathematical tricks to solve the inverse problem and its application to the atomic fountain frequency standard KRISS-F1.

Evaluation of the relativistic redshift in frequency standards at KRISS

“…The uncertainty of N LVD P is relatively smaller than that of GGM because the local data with high precision and resolution were additionally used in the local geoid model. The height of the ECP referenced to W LVD 0 and that referenced to W CGPM 0 are estimated to be 81.030 (32) m and 81.303(33) m, respectively. Using the height difference between the ECP and the atomic clock, the height of the atomic clock is determined to be 75.156 (33).…”

“…At Korea Research Institute of Standards and Science (KRISS), Yb optical lattice clocks [27][28][29][30][31] and Cs fountain clocks [32] have been developed. The first optical lattice clock at KRISS, KRISS-Yb1, has regularly been used since 2021 to calibrate the TAI [33,34].…”