Structures that strongly confine the photons on the scale of the light wavelength have been studied in semiconductor physics for about 20 years, giving rise to a wealth of fundamental studies exploiting the reinforced light-matter (both linear and nonlinear) interaction. Most studies were done in well mastered III-V material systems, which however suffer from some drawbacks such as a low exciton binding energy, low barrier potentials in heterostructures and a transparency window limited to the near infrared. Semiconductors of the III-N family have quite peculiar properties such as a large excitonic binding energy and a transparency window that extends to 200 nm. They are the dominant material family for the fabrication of UV-blue-green optoelectronic devices (laser diodes and light-emitting diodes) as well as for white light production. Nitrides are already massively used for high density optical storage and display light sources but shorter wavelength optoelectronic devices are also potentially very interesting for biochemical sensors, purification, disinfection and medical diagnosis. Interestingly, a current trend consists in integrating III-N materials on silicon. For these reasons, III-N materials are thus expected to play a significant role in novel photonic systems and, in this respect they are very good candidates to probe light-matter interaction in photon confining structures. It is however notorious that III-N semiconductors are difficult to process and this technological drawback has hindered achievements in highly confined optical structures. It is the aim of the QUANONIC project to probe quantum optical and nonlinear effects in AlGaN based high optical quality microdisks and photonic crystal (PC) structures. Based on the know-how of the consortium to fabricate and to probe III-N based microcavities, several goals will be pursued and if successful will represent major breakthroughs for the development of novel optoelectronic devices integrated on silicon. Goal 1 : Microlaser and strong coupling at UV wavelengths in III-N microcavities. Fabrication of optical resonators having high quality factors is now mastered by the consortium. The next issue to address to reach lasing is the optimization of the active region in order to get high gain active medium: our strategy is twofold. i) We will seek to grow GaN/AlN quantum dots (QD) with high oscillator strength and high areal density. A detailed study of microlasing and Purcell effect will be made. ii) By exploiting the large oscillator strength of III-N excitons, high quality factor microcavities will be designed for photon-exciton strong coupling. We shall explore the conditions for strong coupling, both for confined modes and for extended modes in III-N photonic crystals. The ultimate goal will be to reach polariton lasing. Goal 2 : Frequency conversion in III-N photon confining structures for deep UV sources. Thanks to a much wider transparency window than conventional semiconductors and to large nonlinear coefficients, III-N are very good candidates for frequency conversion in confined structures. The photonic crystal geometry allows for large field intensities (cavity enhanced frequency conversion) and also for the tailoring of the refractive properties. Original phase-matching conditions will be demonstrated experimentally, such as backward second harmonic generation (SHG) and “all angle” SHG that are very difficult or impossible to obtain in larger scale periodically poled nonlinear materials. As a final and ambitious objective of the project, we propose an investigation of a compact coupling of semiconductor lasers and frequency converting cavities that enlightens the potentialities of our approach for forthcoming UV optoelectronics. The integration of nitride laser emission and frequency doubling in a III-N photonic structure represents a realistic opportunity to demonstrate an all-semiconductor compact optical source operating in the 200-250 nm wavelength range.