Theory of the multiphoton cascade transitions with two photon links: comparison of Quantum Electrodynamical and Quantum Mechanical approaches

TL;DR

This paper develops a QED theory for multiphoton cascade transitions in atoms and ions, comparing it with a phenomenological quantum mechanical approach for specific processes involving two and three photon emissions.

Contribution

It introduces a comprehensive QED framework for multiphoton cascade transitions and compares it with quantum mechanical methods for the first time.

Findings

QED and quantum mechanical approaches yield consistent results.

Detailed analysis of specific multiphoton transition processes.

Enhanced understanding of photon cascade mechanisms in atomic systems.

Abstract

QED theory of multiphoton cascade transitions in atoms and ions is developed. In particular the $ 3s\rightarrow1s+2\gamma $, $ 4s\rightarrow1s+2\gamma $ and $ 3p\rightarrow1s+3\gamma $ processes are considered. Two different approaches (Quantum Electrodynamical and phenomenological Quantum Mechanical) are applied.