Analytical study of the spiky feature in a two-photon driven lossy ladder system. (2nd September 2019)

• Record Type: Journal Article
• Authors: Wang, Luojia; Xu, Jingping; Yuan, Luqi; Yang, Yaping
• Is Part Of: Laser physics. Volume 29:Number 10(2019)
• Publication Date: 2019-09-02
• Subjects: three-level atomic system -- Maxwell–Bloch equations -- atomic coherence; Lasers -- Periodicals; 621.36605
• DOI: 10.1088/1555-6611/ab3c48
• Languages: English
• ISSNs: 1054-660X

Abstract

Abstract: There has been an experimental report (Traverso et al 2012 Proc. Natl Acad. Sci. USA 109 15185) that oxygen lasing in ambient air exhibits a spiky feature. We theoretically explore a ladder-type three-level atomic system driven by a two-photon resonant pump pulse in a lossy medium, which corresponds to that oxygen experiment. We study the Maxwell–Bloch equations both numerically and analytically and discover that a long pump field brings competition between two mechanisms of coherent pumping and coherent emission, leading to the spiky emission, which cannot be produced using a short pump. The results indicate that atomic coherence occurs in the experiment. Our study provides a clear understanding of the oxygen experiment using a nanosecond pump laser and could lead to the potential application of this oxygen lasing in future experiments.