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arXiv · 1602.02497

Phase matched backward-wave second harmonic generation in a hyperbolic carbon nanoforest

A. K. Popov·I. S. Nefedov·S. A. Myslivets
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Abstract

We show that deliberately engineered spatially dispersive metamaterial slab can enable co-existence and phase matching of contra-propagating ordinary fundamental and backward second harmonic electromagnetic modes. Energy flux and phase velocity are contra-directed in backward waves which determines extraordinary nonlinear-optical propagation processes. Frequencies, phase and group velocities, as well as nanowavequide losses inherent to the electromagnetic modes supported by the metamaterial can be tailored to optimize nonlinear-optical conversion of frequencies and propagation directions of the coupled waves. Such a possibility, which is of paramount importance for nonlinear photonics, is proved with numerical model of the hyperbolic metamaterial made of carbon nanotubes standing on metal surface. Extraordinary properties of backward-wave second harmonic in the THz and IR propagating in the reflection direction are investigated with focus on pulsed regime.

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A. K. Popov, I. S. Nefedov, S. A. Myslivets. 2016-02-08. Phase matched backward-wave second harmonic generation in a hyperbolic carbon nanoforest. https://arxiv.org/abs/1602.02497

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