Photonic crystals (PCs), are famous due to their well-known temporal dispersion properties as well as recently discovered spatial dispersion properties, allowing to manage spatial propagation properties of light. The peculiarities of the spatial propagation in PCs consist in vanishing of diffraction (self-collimation [1,2], negative-refraction and super-refraction of light [3]). The above listed effects refer to the propagation of the beams inside the PCs. Less is understood about the behavior of the beams behind the crystals with nontrivial dispersion properties. The ideas have been promoted that the PCs should show super-lensing effects [4], however, these effects are not well understood theoretically, nor convincingly demonstrated experimentally. We concentrate on the beam propagation behind the PCs and report an experimental observation of the formation of well collimated beam behind the 3D PC of a woodpile type. Our samples of woodpile PCs were fabricated with a femtosecond laser multi-photon polymerization technique by direct 3D writing in polymers with up to 200 nm spatial resolution. The method is described in [5-6]. The photosensitive material was hybrid organic-inorganic Zr containing SZ2080 ensuring high resolution and low geometrical distortions. We used two different samples: 1) high contrast 2) low contrast. The transverse period was 1 μm; the longitudinal periods were 4.5 μm and 4.1 μm for the low and high contrast samples respectively.
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