Improved absolute frequency measurement of the¹⁷¹Yb optical lattice clock at KRISS relative to the SI second

Abstract

We measured the absolute frequency of the $^1S_0$ - $^3P_0$ transition of\n$^{171}$Yb atoms confined in a one-dimensional optical lattice relative to the\nSI second. The determined frequency was 518 295 836 590 863.38(57) Hz. The\nuncertainty was reduced by a factor of 14 compared with our previously reported\nvalue in 2013 due to the significant improvements in decreasing the systematic\nuncertainties. This result is expected to contribute to the determination of a\nnew recommended value for the secondary representations of the second.\n