Parameter estimation in atomic spectroscopy using exceptional points

TL;DR

This paper explores how exceptional points in non-Hermitian quantum systems can be utilized for precise parameter estimation in atomic spectroscopy, demonstrated with rubidium and calcium ion transitions.

Contribution

It introduces a novel approach leveraging exceptional points in non-Hermitian dynamics for enhanced parameter estimation accuracy in atomic spectroscopy.

Findings

Exceptional points occur at specific laser parameters.

The method improves parameter estimation precision.

Demonstrated on rubidium and calcium ion spectra.

Abstract

The dynamics of spontaneous emission of an atomic system is studied in the framework of an open quantum system. The resulting quantum master equation for the atomic system is non hermitian. The generator $\mathcal{L}$ can possess non-hermitian degeneracies, i.e. exceptional points ($EP$), for specific values of the external laser driving amplitude and detuning from the atomic lines. We suggest to employ the special properties of these $EP$s for accurate parameter estimation. The method is demonstrated for the atomic spectrum of $S \rightarrow P$ transitions of $~^{85}$Rb and $~^{40}$Ca$~^+$.