A disadvantage of pure rotational coherent anti-Stokes Raman scattering (CARS) compared with vibrational CARS is the limited dynamic range for temperature measurements. Here an optical configuration is described that overcomes this limitation by the use of two different center-frequency dye lasers in a dual-broadband CARS approach. Its performance is demonstrated for simultaneous pure rotational CARS temperature and relative N<sub>2</sub>–O<sub>2</sub>concentration measurements up to 1950 K at ambient pressure.
© 1998 Optical Society of America
(030.1670) Coherence and statistical optics : Coherent optical effects
(120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
(120.6780) Instrumentation, measurement, and metrology : Temperature
(290.5860) Scattering : Scattering, Raman
(300.6420) Spectroscopy : Spectroscopy, nonlinear
Albert Thumann and Alfred Leipertz, "Dynamic Range Enhancement for Pure Rotational Coherent Anti-Stokes Raman Scattering Thermometry by use of an Optical Arrangement with Two Dye Lasers," Appl. Opt. 37, 2327-2333 (1998)