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arXiv · 0811.4419

Subdiffraction and spatial filtering due to periodic spatial modulation of the gain/loss profile

K. Staliunas·R. Herrero·R. Vilaseca
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Abstract

We investigate light propagation through materials with periodically modulated gain/loss profile in both transverse and longitudinal directions, i.e. in material with two-dimensional modulation in space. We predict effects of self-collimation (diffraction-free propagation) of the beams, as well as superdiffusion (spatial frequency filtering) of the beams in depending on the geometry of the gain/loss lattice, and justify the predictions by numerical simulations of the paraxial wave propagation equations.

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K. Staliunas, R. Herrero, R. Vilaseca. 2008-11-26. Subdiffraction and spatial filtering due to periodic spatial modulation of the gain/loss profile. https://arxiv.org/abs/0811.4419

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