High-resolution isotope-shift spectroscopy of Cd I

TL;DR

This paper provides high-precision isotope shift measurements for cadmium, revealing quantum interference effects, extracting nuclear parameters, and resolving previous measurement discrepancies.

Contribution

It introduces precise isotope shift data for all cadmium isotopes, accounts for quantum interference effects, and determines nuclear charge radii differences.

Findings

Quantum interference causes up to 29(5)MHz error in hyperfine measurements.

Field- and mass-shift parameters are extracted via King-plot analysis.

The lifetime of the ${}^1\text{P}_1$ state is measured as 1.60(5)ns.

Abstract

We present absolute frequency measurements of the ${}^{1}\text{P}_1 \leftarrow {}^{1}\text{S}_0$ ($229$nm) and ${}^{3}\text{P}_1 \leftarrow {}^{1}\text{S}_0$ ($326$nm) transitions for all naturally occurring isotopes of cadmium. The isotope shifts and hyperfine intervals of the fermionic isotopes are determined with an accuracy of 3.3MHz. We find that quantum interference in the laser-induced fluorescence spectra of the ${}^{1}\text{P}_1 \leftarrow {}^{1}\text{S}_0$ transition causes an error of up to 29(5)MHz in determining the hyperfine splitting, when not accounted for with an appropriate model. Using a King-plot analysis, we extract the field- and mass-shift parameters and determine nuclear charge radius differences for the fermions. The lifetime of the $^1\text{P}_1$ state is determined to be 1.60(5)ns by measuring the natural linewidth of the ${}^{1}\text{P}_1 \leftarrow {}^{1}\text{S}_0$ transition. These results resolve significant discrepancies among previous measurements.