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arXiv · 1403.6026

Phase-Insensitive Scattering of Terahertz Radiation

M. Petev·N. Westerberg·E. Rubino·D. Moss·A. Couairon·F. Légaré·R. Morandotti·D. Faccio·M. Clerici
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Abstract

The nonlinear interaction between Near-Infrared (NIR) and Terahertz pulses is principally investigated as a means for the detection of radiation in the hardly accessible THz spectral region. Most studies have targeted second-order nonlinear processes, given their higher efficiencies, and only a limited number have addressed third-order nonlinear interactions, mainly investigating four-wave mixing in air for broadband THz detection. We have studied the nonlinear interaction between THz and NIR pulses in solid-state media (specifically diamond), and we show how the former can be frequency-shifted up to UV frequencies by the scattering from the nonlinear polarisation induced by the latter. Such UV emission differs from the well-known electric-field-induced second harmonic (EFISH) one, as it is generated via a phase-insensitive scattering, rather than a sum- or difference-frequency four-wave-mixing process.

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M. Petev, N. Westerberg, E. Rubino, D. Moss, A. Couairon, F. Légaré, R. Morandotti, D. Faccio, M. Clerici. 2014-03-24. Phase-Insensitive Scattering of Terahertz Radiation. https://arxiv.org/abs/1403.6026

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