Abstract: In recent years, the fabrication of integrated photonic devices based on thin-film lithium niobate (TFLN) has advanced significantly, enabling the realization of increasingly complex optical circuits. This progress could have a profound technological impact, owing to the relatively strong second-order (χ²) nonlinear response of lithium niobate. However, fully exploiting this nonlinearity is far from straightforward, particularly in resonant structures that must operate over broad spectral bandwidths, where the effects of material chromatic dispersion become significant. In the first part of this talk, I will present an approach to highly efficient photon-pair generation across an exceptionally wide spectral range by leveraging the unique properties of linearly uncoupled resonators. In the second part, I will show that, beyond its technological relevance, the TFLN platform also provides a powerful means to investigate the interplay between χ² and χ³ interactions occurring within the same integrated system. This coexistence opens the way to exploring fundamental aspects of quantum interference in nonlinear optical processes.

Bio: Marco Liscidini received the Ph.D. degree in physics from the University of Pavia (Italy) in 2006. From 2007 to 2009, he was a Post-Doctoral Fellow in the group of Prof. J. E. Sipe at the Department of Physics of the University of Toronto, Canada. He is currently Professor at the Department of Physics of the University of Pavia, a member of the Steering Committee of the National Quantum Science and Technology Institute and serves as a technical advisor to Xanadu Quantum Technologies Inc., Toronto, Canada and to Ephos Srl, Milan, Italy. His research activity is focused on the theoretical study and modelling of the light-matter interaction in micro- and nanostructures. He works in several areas of photonics, including classical and quantum nonlinear optics, spontaneous emission, plasmon and QW-exciton polaritons, optical sensing and bio-sensing, and photovoltaic effects. His theoretical research activity is in strong collaboration with experimental groups and in the framework of national, European, US, and Canadian research programs. He is a Fellow of Optica.