Related Experiment Video
Updated: May 18, 2026

Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown
Published on: February 14, 2014
Observing superradiant decay of excited-state helium atoms inside helium plasma
Hui Xia1, Anatoly A Svidzinsky, Luqi Yuan
1Princeton University, Princeton, New Jersey 08542, USA.
Abstract:
Using femtosecond transient absorption spectroscopy on excited-state helium atoms in a plasma created through optical field ionization, we measured the decay of 2(3)S-2(3)P excitation with sub-ps temporal resolution. The population evolution shows that initial decay is significantly faster than the electron-atom collisions and three orders of magnitude faster than the single atom spontaneous decay rate. This indicates on superradiant coherent behavior of the atomic system inside the plasma.
Related Concept Videos
Atomic Emission Spectroscopy: Overview
Atomic Emission Spectroscopy: Lab
Inductively Coupled Plasma Atomic Emission Spectroscopy: Principle
The ions and electrons produced interact with the fluctuating magnetic field created by a water-cooled...
Emission Spectra
Atomic Emission Spectroscopy: Instrumentation
Types of Radioactivity
Alpha (α) decay is the emission of an α particle from the nucleus. For example, polonium-210 undergoes α decay:

