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arXiv · 0803.2937

Standoff Detection of Solid Traces by Single-Beam Nonlinear Raman Spectroscopy Using Shaped Femtosecond Pulses

O. Katz·A. Natan·S. Rosenwaks·Y. Silberberg
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Abstract

We demonstrate a single-beam, standoff (>10m) coherent anti-Stokes Raman scattering spectroscopy (CARS) of various materials, including trace amounts of explosives and nitrate samples, under ambient light conditions. The multiplex measurement of characteristic molecular vibrations with <20cm-1 spectral resolution is carried out using a single broadband (>550cm-1) phase-shaped femtosecond laser pulse. We exploit the strong nonresonant background signal for amplification of the weak backscattered resonant CARS signal by using a homodyne detection scheme. This facilitates a simple, highly sensitive single-beam spectroscopic technique, with a potential for hazardous materials standoff detection applications.

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O. Katz, A. Natan, S. Rosenwaks, Y. Silberberg. 2008-03-20. Standoff Detection of Solid Traces by Single-Beam Nonlinear Raman Spectroscopy Using Shaped Femtosecond Pulses. https://doi.org/10.1063/1.2918014

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