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Photon-pair sources based on spontaneous parametric down-conversion (SPDC) are the backbone of a vast number of experimental implementations in quantum optics. Sub-wavelength-sized dielectric nanoresonators have recently emerged as a new platform for the implementation of SPDC sources [1] , that promise much potential in generating photons with engineered properties, as these nanoresonators offer a strong control over many parameters of the scattered light (directionality, polarization, …) However, the many degrees of freedom in these highly multi-modal and non-Hermitian systems makes design and formal description of pair-generation challenging.

All-dielectric nanophotonics has recently raised an increasing interest because the optical response of high-permittivity dielectric nanoparticles exhibits negligible dissipative losses and strong magnetic multipole resonances [1–4] in the visible and near-IR. We recently reported a second harmonic generation (SHG) conversion efficiency higher than 10−5 at 2 = 1554 nm (pump intensity ≈ 1.6 GW/cm2; pulse width ≈ 150 fs; repetition rate = 80 MHz) in all-dielectric Al 0.18 Ga 0.82 As-on-AlOx nanodisks [5–7]. Such a remarkable efficiency is achieved thanks to the exploitation of magnetic and electric resonances emerging at coincidence with both the pump and SHG wavelength. In addition, the choice of both the pump and, consequently, the SHG (≈ 777 nm) wavelength, set below the energy of the material bandgap, allow minimizing the two-photon absorption of the pump and the re-absorption of the SHG.

All-dielectric and semiconductor nonlinear nanophotonics is an emerging field enabling efficient optical interactions between magnetic and electric resonances at sub-wavelength scales, thereby achieving high directionality and high figures of merit due to very low losses [1, 2]. It was shown that AlGaAs nanodisks with quadratic nonlinear susceptibility can provide second harmonic generation (SHG) with record-high efficiency of 10−4 [3], opening to a wide range of possible applications, including nonlinear microscopy and holography. In this work, we show experimentally that the strong quadratic nonlinearity in AlGaAs nano-disks allows efficient sum-frequency generation (SFG) with nontrivial polarization dependencies. By using the established classical-quantum analogy [4], we predict that these nano-resonators can facilitate efficient generation of quantum entangled photon pairs with higher than kHz biphoton rate and strong angular correlations.

In this talk, we numerically demonstrate the potential of a hyperbolic medium in the design of an efficient metamaterial antenna enhancing the second harmonic generation of a nano-object, with an otherwise hidden nonlinear signature through a metamaterial-assisted access to evanescent second-harmonic fields. In further discussion, we consider the second harmonic generation from the metamaterial itself and report the criterion of its efficiency.

In this talk, we will overview nonlinear plasmonic effects due to intrinsic, hydrodynamic metal nonlinearity, enhanced by sub-wavelength field confinement, interaction between plasmonic resonances and nonlocal effects. In particular, various nonlinear effects, such as nonlinear mode coupling, high-order harmonics and coherent supercontinuum generation will be discussed.

Plasmonic metamaterials and metasurfaces open up possibility to design the enhanced second- and third-order nonlinear optical properties in a desired spectral range beyond nonlinear optical response of their constituents. Here we overview optical nonlinearities and optomechanical effects enabled by metamaterials.

Real-time 3D content distribution over a network (either LAN or WAN) has many possible applications, but requires facing several challenges, most notably the handling of the large amount of data usually associated with 3D meshes. The scope of the present paper falls within the well-established context of real-time capture and streaming of OpenGL command sequences, focusing in particular on data compression schemes. However, we advance beyond the state-of-the-art improving over previous attempts of "in-frame" geometric compression on 3D structures inferred from generic OpenGL command sequences and adding "inter-frame" redundancy exploitation of the traffic generated by the typical architecture of interactive applications. Measurements reveal for this combination of techniques a very effective reduction of network traffic and a CPU overhead compatible with the requirements of interactive applications, suggesting a significant application potential for Internet-based 3D content streaming.

Real-time 3D content distribution over a network requires facing several challenges, most notably the handling of the large amount of data usually associated with 3D meshes. The scope of the present paper falls within the well-established context of real-time capture and streaming of OpenGL command sequences, focusing in particular on data compression schemes. However, we advance beyond the state-of-the-art improving over previous attempts of “in-frame” geometric compression on 3D structures inferred from generic OpenGL command sequences and adding “inter-frame” redundancy exploitation of the traffic generated by the typical architecture of interactive applications.