Detaled description of spontaneous emission

TL;DR

This paper calculates the electromagnetic field of spontaneous emission from laser-excited atoms and polyatomic sources using atomic quantum electrodynamics, revealing coherence and superradiance phenomena and explaining natural light randomness.

Contribution

First-principles calculation of spontaneous emission EMF using a simple atomic quantum electrodynamics method, demonstrating coherence and superradiance in light sources.

Findings

SE can be coherent in laser-excited sources

Small sources of SE can be superradiant

Natural light randomness is due to thermal excitation

Abstract

The wave side of wave-photon duality, describing light as an electromagnetic field (EMF), is used in this article. EMF of spontaneous light emission (SE) of laser excited atom is calculated from first principles for the first time. This calculation is done using simple method of atomic quantum electrodynamics. EMF of SE is calculated also for three types of polyatomic light sources excited by laser. It is shown that light radiated by such sources can be coherent, which explains recent experiments on SE of laser excited atoms. Small sources of SE can be superradiant, which also conforms to experiment. Thus SE is shown not to be a random event itself. Random properties of natural light are simply explained as a result of thermal excitation randomness without additional hypotheses. EMF of SE is described by simple complex functions but not real ones.