MechE Colloquium: Versatile light generation and manipulation in engineered nonlinear optical waveguides


Event details

Date and time 20.04.2021 12:1513:15  
Speaker Prof. Camille Brès, Photonic Systems Laboratory (PHOSL), EPFL School of Engineering (STI), Institute of Electrical Engineering (IEL)
Category Conferences - Seminars
Nonlinear optics describes the behaviour of light in a nonlinear medium, exploiting higher orders of the material susceptibility. It allows us to, for example, change the colour of a light beam, change its shape and or process light with light. Nonlinear optical phenomena are the basis of many devices used in optical communication systems, optical sensing or material research. They also enable a wide range of novel applications, from time keeping, to searching for exoplanet or quantum computing. The need for the integration of nonlinear functionalities to the waveguide or chip scale is evident: it is the only path towards optical signal processing devices that are portable, compact, power efficient and user-friendly.

In this talk, we present our approaches for improving the efficiency and versatility of optical nonlinear effects in waveguiding system. We will describe how leveraging intrinsic material properties combined with optimized waveguide geometries and system’s engineering can enhance the performance of devices used for light generation or signal processing [1]. We show how microstructures, either in fibers or integrated designs, provide a powerful method for shaping a favourable dispersion landscape necessary for controlling nonlinear interactions and opening new possibilities in terms of sensing, quantum and light generation [2-4]. We will also explain how novel nonlinear functionalities can be introduced in silicon-photonic platforms [5,6] and conclude with some outlook on further challenges and possibilities.

[1] S. Xing, D. Grassani, S. Kharitonov, A. Billat, C-S Brès, ‘Characterization and modeling of microstructured chalcogenide fibers for efficient mid-infrared wavelength conversion,’ Optics Express 24 (9), 9741-9750 (2016)

[2] S. Xing, et al., ‘Mid-infrared continuous-wave parametric amplification in chalcogenide microstructured fibers,’ Optica 4 (6), 643-648 (2017)

[3] E. Nitiss, O. Yakar, A. Stroganov, C.-S. Brès, ‘Highly tunable second-harmonic generation in all-optically poled silicon nitride waveguides, Optics letters 45 (7), 1958-1961 (2020)

[4] D. Grassani, et al., ‘Mid infrared gas spectroscopy using efficient fiber laser driven photonic chip-based supercontinuum,’ Nature Communications 10 (1), 1-8 (2019)

[5] A. Billat, et al., ‘Large second harmonic generation enhancement in Si3N4 waveguides by all-optically induced quasi-phase-matching,’ Nature Communications 8 (1), 1-7 2017 (2017)

[6] E. Nitiss, T. Liu, D. Grassani, M. Pfeiffer, T.J. Kippenberg, C.-S. Brès, ‘Formation Rules and Dynamics of Photoinduced χ(2) Gratings in Silicon Nitride Waveguides,’ ACS Photonics 7 (1), 147-153 (2019)

Camille-Sophie Brès is an associate professor at EPFL in the institute of Electrical Engineering. She received her bachelor degree with honors in EE from McGill University, Canada, in 2002. She then moved to the USA where she obtained her PhD in EE from Princeton University in 2006. After a post-doctoral position at the University of California San Diego she joined EPFL as a tenure track professor and director of the Photonic Systems Laboratory in 2011. Her work focusses on leveraging and enhancing nonlinear processes in optical waveguides for the optimization of all-optical signal processing, light generation and sensing by exploiting dispersion engineering, material properties, and architectural features. She was awarded the early career Women in Photonics Award from the European Optical Society in 2016, as well as ERC starting (2012), Consolidator (2017) and Proof of Concept (2019) grants.