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arXiv · 1202.4585

High-Directional Wave Propagation in Periodic Gain/Loss Modulated Materials

N. Kumar·M. Botey·R. Herrero·Yu. Loiko·K. Staliunas
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Abstract

Amplification/attenuation of light waves in artificial materials with a gain/loss modulation on the wavelength scale can be sensitive to the propagation direction. We give a numerical proof of the high anisotropy of the gain/loss in two dimensional periodic structures with square and rhombic lattice symmetry by solving the full set of Maxwell's equations using the finite difference time domain method. Anisotropy of amplification/attenuation leads to the narrowing of the angular spectrum of propagating radiation with wavevectors close to the edges of the first Brillouin Zone. The effect provides a novel and useful method to filter out high spatial harmonics from noisy beams.

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N. Kumar, M. Botey, R. Herrero, Yu. Loiko, K. Staliunas. 2012-02-21. High-Directional Wave Propagation in Periodic Gain/Loss Modulated Materials. https://doi.org/10.1016/j.photonics.2012.06.003

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