Absolute frequency measurements for hyperfine structure determination of the R(26) 62-0 transition at 501.7 nm in molecular iodine

TL;DR

This paper reports the first absolute frequency measurements of hyperfine components of a specific iodine transition at 501.7 nm using a femtosecond laser frequency comb, achieving high precision.

Contribution

It introduces a novel measurement of hyperfine frequencies in molecular iodine with an optical clockwork and femtosecond laser comb, providing high accuracy data.

Findings

Measured hyperfine components with 250 Hz uncertainty

Achieved a linewidth of 45 kHz in resonance detection

First absolute frequency measurements for this transition

Abstract

The absolute frequencies of the hyperfine components of the R(26) 62-0 transition in molecular iodine at 501.7 nm are measured for the first time with an optical clockwork based on a femtosecond laser frequency comb generator. The set-up is composed of an Ar+ laser locked to a hyperfine component of the R(26) 62-0 transition detected in a continuously pumped low-pressure cell (0.33 Pa). The detected resonances show a linewidth of 45 kHz (half-width at half-maximum). The uncertainty of the frequency measurement is estimated to be 250 Hz.