Single-shot single-beam coherent Raman scattering thermometry based on optically induced air lasing

Area of Science:

• Physics
• Optical diagnostics
• Spectroscopy

Background:

• Accurate, fast, and easy-to-implement thermometric techniques are crucial for studying dynamic combustion, transient reacting flows, and non-equilibrium plasmas.
• Existing methods may face limitations in speed, accuracy, or complexity for these demanding applications.

Purpose of the Study:

• To develop a novel single-shot, single-beam coherent Raman scattering (SS-CRS) thermometry technique.
• To utilize air lasing as a probe for enhanced signal quality and measurement speed.

Main Methods:

• Development of a single-shot, single-beam coherent Raman scattering (SS-CRS) system.
• Integration of air lasing as a probe beam to enhance the signal-to-noise ratio.
• Validation of the SS-CRS thermometry across various temperatures.

Main Results:

• The air-lasing-assisted SS-CRS demonstrated a high signal-to-noise ratio, enabling single-shot measurements at a 1 kHz repetition rate.
• The SS-CRS thermometry achieved a precision of less than 2.3%, with inaccuracy increasing at higher temperatures.
• Unique characteristics of air lasing facilitated high measurement repeatability and a fast acquisition rate.

Conclusions:

• The developed SS-CRS thermometry, powered by air lasing, provides a novel and effective approach for high-speed temperature measurements.
• This technique holds significant potential for advanced diagnostics in transient reacting flows and plasmas.
• The ease of implementation and high performance open new avenues for rapid thermometric analysis.