The last couple of years have witnessed an unprecedented boost in nonlinear nanophotonics, allowed both by constant technological evolution in the fabrication of integrated micro- and nano-structures, and by a deeper understanding of multipolar magnetic and electric response of all-dielectric sub-wavelength nanoparticles. Besides reviewing the recent progress in the hybrid and monolithic semiconductor platforms that are being employed to demonstrate parametric sources on chip, we will focus on high-contrast nonlinear nanophotonic sources in the near-infrared spectral region, where plasmonic devices fall short of broad applicability. To confine photons at the nanoscale by total internal reflection, metal-less devices rely on a high-refractive-index core surrounded by low-index cladding in one or more dimensions, and therefore they typically consist of semiconductor nanostructures that either lie on an oxide substrate or are suspended in air. We will report on our results on χ(2) AlGaAs suspended nanowires  and AlGaAs-on-AlOx nanoantennas , with a perspective view on collective nonlinear effects in 1D and 2D arrays. Finally we will comment on the most sought applications of integrated parametric sources, including optical frequency comb generators and optical parametric oscillators on-chip with sub-milliwatt threshold.
 N. Morais, I. Roland, M. Ravaro, I. Favero, A. Lemaître, S. Wabnitz, M. De Rosa, and G. Leo, SPIE Nanophotonics Australasia 2017, Melbourne 10-13/12/2017.
 V. F. Gili, L. Carletti, A. Locatelli, D. Rocco, M. Finazzi, L. Ghirardini, I. Favero, C. Gomez, A. Lemaître, M. Celebrano, C. De Angelis, and G. Leo, Opt. Express 24, 15965 (2016).