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Controlling the Polarization of Nitrogen Ion Lasing
Jingsong Gao1, Xiang Zhang2, Yang Wang1
1State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China.
The Journal of Physical Chemistry Letters
|April 1, 2024
Summary
Researchers have uncovered the mechanism behind nitrogen (N2+) lasing polarization. The study reveals that pump light alignment of N2+ ions dictates the lasing output polarization, enabling control over this atmospheric laser phenomenon.
Area of Science:
- Atmospheric physics
- Laser science
- Quantum electronics
Background:
- Air lasing offers remote coherent radiation generation in the atmosphere.
- Polarization properties of N2+ lasing remain poorly understood, exhibiting confusing behaviors.
Purpose of the Study:
- To experimentally and theoretically investigate N2+ lasing polarization.
- To reveal the underlying physical mechanism governing N2+ lasing polarization.
Main Methods:
- Experimental investigation of N2+ lasing.
- Theoretical modeling and analysis.
- Numerical reproduction of experimental observations.
Main Results:
- Optical gain in N2+ lasing is anisotropic due to pump-induced preferential ionization and alignment of N2+.
- Lasing polarization aligns with pump light polarization after amplification.
- Alignment effect intensifies with increasing amplification factor.
Conclusions:
- Permanent alignment of N2+ ions is the key mechanism controlling lasing polarization.
- A theoretical model successfully explains and reproduces experimental findings.
- Identified key factors for controlling N2+ lasing polarization.
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