AUTHOR=Peng Tao , Zhao Xingchen , Shih Yanhua , Scully Marlan O. 

TITLE=High Order Coherence Functions and Spectral Distributions as Given by the Scully-Lamb Quantum Theory of the Laser

JOURNAL=Frontiers in Physics

VOLUME=9

YEAR=2021

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2021.657333

DOI=10.3389/fphy.2021.657333

ISSN=2296-424X

ABSTRACT=<p>We propose and demonstrate a method for measuring the time evolution of the off-diagonal elements ρ<sub><italic>n,n</italic>+<italic>k</italic></sub>(<italic>t</italic>) of the reduced density matrix obtained from the quantum theory of the laser. The decay rates of the off-diagonal matrix element ρ<sub><italic>n,n</italic>+<italic>k</italic></sub>(<italic>t</italic>) (k = 2,3) are measured for the first time and compared with that of ρ<sub><italic>n,n</italic>+1</sub>(<italic>t</italic>), which corresponds to the linewidth of the laser. The experimental results agree with the Scully-Lamb quantum theory of the laser.</p>