Radiative properties of rubidium atoms trapped in solid neon and parahydrogen

TL;DR

This study investigates the radiative properties of rubidium atoms trapped in solid neon and parahydrogen, focusing on their potential for quantum sensing and measuring fluorescence and lifetimes.

Contribution

It provides the first measurements of laser-induced fluorescence and excited state lifetime of rubidium in solid neon, and sets upper limits for fluorescence in solid parahydrogen.

Findings

No fluorescence detected in parahydrogen, with upper limits established.

Laser-induced fluorescence observed in neon, with spectral and lifetime measurements.

Atoms bleach under excitation light, affecting fluorescence stability.

Abstract

It is known from ensemble measurements that rubidium atoms trapped in solid parahydrogen have favorable properties for quantum sensing of magnetic fields. To use a single rubidium atom as a quantum sensor requires a technique capable of efficiently measuring the internal state of a single atom, such as laser-induced fluorescence. In this work we search for laser-induced fluorescence from ensembles of rubidium atoms trapped in solid parahydrogen and, separately, in solid neon. In parahydrogen we find no evidence of fluorescence over the range explored, and place upper limits on the radiative branching ratio. In neon, we observe laser induced fluorescence, measure the spectrum of the emitted light, and measure the excited state lifetime in the matrix. Bleaching of atoms from the excitation light is also reported.