High spectral resolution multiplex CARS spectroscopy using chirped pulses
نویسندگان
چکیده
A simple technique for achieving high spectral resolution coherent anti-Stokes Raman scattering (CARS) spectra with a femtosecond laser system is presented. A linearly chirped and stretched ( 10 ps) pump pulse generates CARS signal only when overlapped in time with the Stokes pulse (90 fs), creating a ‘temporal slit’ that defines the spectral resolution of the technique. Multiplex CARS spectra for liquid methanol and liquid isooctane are presented, demonstrating a spectral resolution of better than 5 cm . This new chirped (c-CARS) technique should prove useful for chemically-selective imaging applications, as it significantly reduces the non-resonant background contribution. 2004 Elsevier B.V. All rights reserved.
منابع مشابه
Chirped coherent anti-stokes Raman scattering for high spectral resolution spectroscopy and chemically selective imaging.
We describe a simple multiplex vibrational spectroscopic imaging technique based on employing chirped femtosecond pulses in a coherent anti-Stokes Raman scattering (CARS) scheme. Overlap of a femtosecond Stokes pulse with chirped pump/probe pulses introduces a temporal gate that defines the spectral resolution of the technique, allowing single-shot acquisition of high spectral resolution CARS s...
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