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We demonstrate optical rogue waves as a consequence of enhanced focusing of caustic networks due to linear propagation in weakly scattering 2D tailored disorder in nonlinear photorefractive systems, and discuss the conditions for extreme amplitudes.

We explore a novel ferroelectric domain engineering approach based on infrared femtosecond laser lithography and thermal control. Various nonlinear photonic structures are created without any external electric field in the volume of lithium niobate.

We realize a portfolio of higher-order cuspoid and umbilic caustics, exploit them as fabricating light for advanced nonlinear photonic structures, and demonstrate nonlinear light propagation therein.

We explore a ferroelectric domain inversion process that is based on a combination of femtosecond laser lithography and thermal control. Arbitrary 2D ferroelectric domain structures are created in the whole crystal without external electric field.

We fabricate elliptic umbilic caustics photonic structures in photosensitive media. The lattice morphs from hexagonal patterns to a single hot spot. We demonstrate experimentally the formation of a soliton in these elliptic umbilic lattices.

In this contribution we demonstrate for the first time to our knowledge a three-dimensional monitoring of the evolution of the spontaneous polarization (Ps) during electrical poling and temperature annealing in multi-domain strontium barium niobate using Cerenkov-type second-harmonic generation.

We transfer higher order caustic catastrophes to optics, thus extending Airy and Pearcey by paraxial swallowtail and butterfly beams. Their caustics provide outstanding light trajectories for optical induction of refractive index structures.

We propose a method for efficient second-harmonic beam shaping in lithium niobate employing volume diffraction holograms induced by femtosecond laser lithography. The amplitude of the fundamental wave is shaped by the diffraction at the hologram. The zeroth and one higher diffraction order of the fundamental wave fulfill the noncollinear phase matching condition leading to second-harmonic generation in a large wavelengths range between 1074 nm and 2500 nm. We demonstrate the generation of SHG vortices with desired topological charges.

We study experimentally and theoretically the relative relationship between the non-zero components of the χ(2)-tensor in dependence of different degrees of ferroelectric domain disorder in quadratic media for frequency doubling and cascaded third harmonic generation.

We report monolithic fabrication of quasi phase-matching waveguides in lithium niobate by direct femtosecond laser writing. The circular type-II waveguide with an embedded multiscan grating enables efficient second harmonic generation of 1064 nm radiation.

Within the topical field of three-dimensional holographic beam shaping, the modulation of complex light fields in amplitude, phase and polarization is demonstrated. Different kinds of higher order modes will be discussed and applied in optical micro-manipulation.

We study the propagation of tailored wave packets in a computer controlled photo-induced disorder. Disorder correlations cause in real space a ballistic front of exponential Anderson Localization, and novel effects are observed in Fourier space.

Twisted waveguide arrays are realized as refractive index structures using tailored three-dimensionally modulated light fields. Probed with discrete vortices of opposed topological charges, this system provides distinctive output states, additionally controllable by the writing power.

We present observation and analysis of universal wave localization effects − Anderson localization and, for the first time, coherent backscattering in photonic random potential ensembles where naturally particular constructive interference contributions survive against statistical speckle background.

We analyze the polarization properties of three Cerenkov-type second-harmonic (CSH) signals in a crystal with a random distribution of the χ(2) nonlinearity. Applications in CSH microscopy for three-dimensional domain visualization are discussed.

We demonstrate conical diffraction in photonic Lieb lattices in fused silica glass. In contrast to Dirac fermions in photonic graphene here the conical intersections with flat band in lattice spectrum support eigenstates with integer pseudospin.

We report integration of two-dimensional waveguide Bragg gratings that support low loss, polarization independent guiding and tunable reflection spectra around λ=1.55 μm. Effective nonlinear coefficients of r13=7.73 pm/V and r33=25.62 pm/V are shown.

Noncollinear second-harmonic generation is induced by a volume grating which is directly written into a lithium niobate wafer by femtosecond laser pulses. The efficiency can be increased by Bragg matching of the fundamental wave.

We report integration of complex waveguides and embedded Bragg gratings in lithium niobate by direct femtosecond laser writing. The core region of a low loss two-dimensional wave-guide structure is modulated periodically using a multiscan technique.

We present the first experimental observation of spatial solitons in a photorefractive photonic curvilinear Weber lattice. The existence as well as the propagation dynamics of the soliton is shown experimentally as well as numerically.

We study experimentally and theoretically the Čerenkov-type second-harmonic generation in a one-dimensional nonlinear photonic crystal. We demonstrate that the power of emitted second-harmonic can be enhanced 270 times by varying the angle of incidence of the fundamental beam such that the reciprocal lattice vector of the crystal can be used to compensate for the phase mismatch in the transverse direction enabling interaction in the nonlinear Bragg diffraction regime.

We present an all-optical method for the creation of large-scale particle arrays on the surface of electro-optic crystals. Manipulation of matter is achieved by dielelectrophoretic forces exhibited by the strong internal fields of these materials.

Based on different families of nondiffracting beams, we demonstrate a novel approach for optical induction of complex photonic structures. This new method allows for the generation of optically induced Bessel, Mathieu, and parabolic photonic lattices.

We explore the symmetry reduction of spatial solitons supported by photonic lattices of three- and four-fold symmetries due to the photorefractive orientational anisotropy. Influences of anisotropy to more complex vortex and multi-vortex solitons are discussed.

Bismuth tellurite is a material for holographic data storage that accomplishes non-volatile readout of holograms. New dopants have been introduced to enhance the photorefractivity. Build-up and decay of the gratings are examined under continous illumination.

Phase-code multiplexing is used to index the reference wave in volume holographic data storage. We present unitary and deterministic non-orthogonal multilevel phase-codes that facilitate increased storage capacities.

We study theoretically and investigate experimentally nonlinear photonic lattices of different symmetries generated by pixel-like solitons in a photorefractive medium. The light-induced periodically modulated nonlinear refractive index is highly anisotropic and nonlocal, and it depends on the lattice orientation relative to the optical axis of the crystal. We discuss the stability of these induced photonic structures and their guiding properties.

In this contribution, we present a photorefractive lithium-niobate novelty filter microscope. We derive conditions, based on the photorefractive model by Kukhtarev et al. [1], for simulating the two-beam coupling functionality in a lithium-niobate crystal. We verify them experimentally by measuring phase changes due to the mixing of equally transparent fluids in a micro-channel using this novelty filter microscope.

We describe soliton localization through combined effects of total internal and Bragg reflection along the principal directions of a square lattice, and study generation of these reduced-symmetry states experimentally through quasi-collapse of phase-engineered elliptic beams.

We experimentally and numerically investigate the modulation instability of incoherent optical beams in photorefractive media. Due to material anisotropy the modulation instability occurs successively from formation of stripes at a first threshold to full two dimensional filaments at a second threshold. We study the dependence of these onsets on the coherence properties of the beam. We derive experimental thresholds for modulation instability from contrast measurements and compare experimental and numerical results.

We describe theoretically stable propagation of two-dimensional nonlinear periodic lattices in saturable self-focusing nonlinear media. Such stationary nonlinear periodic structures were observed experimentally for different lattice periods in the range of 30-100 micro m.