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arXiv · 1510.01297

Nonlinear Electromagnetic Interactions in Energetic Materials

M. A. Wood·D. A. R. Dalvit·D. S. Moore
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Abstract

We study the scattering of electromagnetic waves in anisotropic energetic materials. Nonlinear light-matter interactions in molecular crystals result in frequency-conversion and polarization changes. Applied electromagnetic fields of moderate intensity can induce these nonlinear effects without triggering chemical decomposition, offering a mechanism for non-ionizing identification of explosives. We use molecular dynamics simulations to compute such two-dimensional Raman spectra in the terahertz range for planar slabs made of PETN and ammonium nitrate. We discuss third-harmonic generation and polarization-conversion processes in such materials. These observed far-field spectral features of the reflected or transmitted light may serve as an alternative tool for stand-off explosive detection.

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M. A. Wood, D. A. R. Dalvit, D. S. Moore. 2015-10-05. Nonlinear Electromagnetic Interactions in Energetic Materials. https://doi.org/10.1103/physrevapplied.5.014004

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