The manifold photophysical properties of polar oxide crystals have driven the research field of photorefraction for decades to a large extent. With the availability of nanoscale polar oxide model systems, the question arises to what extent the acquired knowledge remains applicable for crystals with dimensions on length scales of micro- and nanometres, i.e. in the order of magnitude of the...
Lithium niobate is nowadays one of the most used ferroelectrics oxides in the realization of optical modulators, waveguides and optical sensor due to its large acousto-optical, electro-optical and nonlinear optical coefficients. Further tailoring of these applications requires a deeper scientific insight to the relation between the microscopic structure and the macroscopic observables.
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Harmonic nanoparticles (HNPs) are of wide spread interest in the context of material science applications due to their large nonlinear optical (NLO) tensorial elements and their broad spectral tunability [1]. Regarding the investigation of time-dependent phenomena, however, a detailed knowledge of the pulse propagation in such a strongly scattering medium is required. This has so far only been...
Slow light has been observed in several physical systems, including optical fiber, and photorefractive (PR) media. The ability to slow down light pulses is a fascinating phenomenon with important applications, such as optical telecommunications. For that, it is essential that the slow light phenomenon has a large bandwidth, so that it can respond quickly to the short light pulses that will...
Commercial Ge-doped silica fibers can be converted into frequency doublers, despite the lack of quadratic nonlinearity of the glass, by employing optical poling. With this technique, injecting high-intensity fundamental frequency pulses into the fiber generates photoinduced currents leading to a static electric field resulting in an effective second-order nonlinearity that satisfies the...
Due to their unique profiles and fascinating propagating phenomena unconventional beams like Airy beams are good candidates for photo-inducing waveguiding structures in a photorefractive medium. Bessel beams (BBs) share similar features with Airy beams, such as diffraction-free, multi-lobes profiles, and self-trapping property under nonlinear conditions. Thus, several studies on waveguides...
Internal conical diffraction is a well-known singular phenomenon observable whenever a tightly focused wave is incident with its wavevector along one of the two optical axes of an optically biaxial crystal. The effect gives rise to a vector type wave with the Poynting vectors associated to each linear polarization component lying on a slanted cone surface with circular base. The number of...
