A neutral atom frequency reference in the deep UV with 10^(-15) range uncertainty

TL;DR

This paper reports a highly precise measurement of the 199Hg atomic clock transition frequency in the deep UV, achieving an uncertainty of 5.7×10^(-15) and demonstrating a high atomic quality factor.

Contribution

It introduces a new measurement of the 199Hg clock transition with significantly reduced uncertainty and a novel experimental setup using only three laser wavelengths.

Findings

Frequency measured as 1,128,575,290,808,162.0 Hz

Achieved a quality factor Q of approximately 10^14

Uncertainty reduced by nearly three orders of magnitude

Abstract

We present an assessment of the (6s^{2})1S0 -> (6s7s)3P0 clock transition frequency in 199Hg with an uncertainty reduction of nearly three orders of magnitude and demonstrate an atomic quality factor, Q, of ~10^(14). The 199Hg atoms are confined in a vertical lattice trap with light at the newly determined magic wavelength of 362.5697 +/-0.0011 nm and at a lattice depth of 20Er. The atoms are loaded from a single stage magneto-optical trap with cooling light at 253.7 nm. The high Q factor is obtained with an 80 ms Rabi pulse at 265.6 nm. The frequency of the clock transition is found to be 1 128 575 290 808 162.0 +/-6.4 (sys.) +/-0.3 (stat.) Hz (fractional uncertainty = 5.7x10^(-15)). Neither an atom number nor second order Zeeman dependence have yet to be detected. Only three laser wavelengths are used for the cooling, lattice trapping, probing and detection.