Prof. Gustavo Wiederhecker, Unicamp, Campinas, Brazil

Leuchs-Russell Auditorium, A.1.500, Staudtstr. 2

Location Details

Abstract:
Integrated photonics enable compact and energy-efficient control of light for communication, sensing, and emerging quantum technologies. In this talk, I will discuss how nanophotonic circuits confine light so tightly that nonlinear optical and mechanical effects become strikingly strong. Using high-Q microresonators, our group demonstrates chip-scale optical frequency combs [1], [2] and degenerate optical parametric oscillators based on coupled “photonic molecules” [3], [4]. These devices achieve on-chip phase control and dispersion tuning, key for coherent photonic computing and random-number generation. We also explore how light interacts with sound in the context Brillouin optomechanics in lithium-niobate [5] and silicon-based photonic structures[6], [7], [8], revealing new pathways for narrow-linewidth lasers, signal processing, and quantum transduction. Together, these results highlight how integrated nonlinear and optomechanical photonics can link classical and quantum information systems in the next generation of photonic technologies.

References:
1. Fujii, L., Inga, M., Soares, J. H., Espinel, Y. A. V., Mayer Alegre, T. P., & Wiederhecker, G. S. (2020). Dispersion tailoring in wedge microcavities for Kerr comb generation. Optics Letters, 45(12), 3232. https://doi.org/10.1364/ol.393294
2. Inga, M., Fujii, L., da Silva Filho, J. M. C., Quintino Palhares, J. H., Ferlauto, A. S., Marques, F. C., Mayer Alegre, T. P., & Wiederhecker, G. (2020). Alumina coating for dispersion management in ultra-high Q microresonators. APL Photonics, 5(11), 116107. https://doi.org/10.1063/5.0028839
3. Primo, A. G., Carvalho, N. C., Kersul, C. M., Frateschi, N. C., Wiederhecker, G. S., & Alegre, T. P. M. (2020). Quasinormal-Mode Perturbation Theory for Dissipative and Dispersive Optomechanics. Physical Review Letters, 125(23), 233601. https://doi.org/10.1103/PhysRevLett.125.233601
4. Primo, A. G., Pinho, P. V, Benevides, R., Gröblacher, S., Wiederhecker, G. S., & Alegre, T. P. M. (2023). Dissipative optomechanics in high-frequency nanomechanical resonators. Nature Communications, 14(1), 5793. https://doi.org/10.1038/s41467-023-41127-7
5. Rodrigues, C. C., Kersul, C. M., Primo, A. G., Lipson, M., Alegre, T. P. M., & Wiederhecker, G. S. (2021). Optomechanical synchronization across multi-octave frequency spans. Nature Communications, 12(1), 5625. https://doi.org/10.1038/s41467-021-25884-x
6. Rodrigues, C. C., Schilder, N. J., Zurita, R. O., Magalhães, L. S., Shams-Ansari, A., Santos, F. J. L. dos, Paiano, O. M., Alegre, T. P. M., Lončar, M., & Wiederhecker, G. S. (2025). Cross-Polarized Stimulated Brillouin Scattering in Lithium Niobate Waveguides. Physical Review Letters, 134(11), 113601. https://doi.org/10.1103/PhysRevLett.134.113601
7. Souza, M. C. M. M., Rezende, G. F. M., Barea, L. A. M., Wiederhecker, G. S., & Frateschi, N. C. (2016). Modeling quasi-dark states with temporal coupled-mode theory. Optics Express, 24(17), 18960–18972. https://doi.org/10.1364/OE.24.018960
8. Tomazio, N. B., Trinchão, L. O., Gonçalves, E. S., dos Santos, L. F., Santos, F. G. S., Jarschel, P. F., Alegre, T. P. M., & Wiederhecker, G. S. (2025). Tunable Degenerate Optical Parametric Oscillation with Coupled Microresonators. ACS Photonics, 12(1), 227 – 235. https://doi.org/10.1021/acsphotonics.4c01559

Bio:
Gustavo Wiederhecker is an Associate Professor at Unicamp, Brazil, with a B.Sc. and Ph.D. in Physics (2008) from the same institution and postdoctoral experience at Cornell University (2008-2011). He has co-authored over 50 research papers related to nonlinear optical phenomena in microphotonic devices, with special focus on light-mechanical wave interactions. He served as the topical editor for JOSA B (nanophotonics, optomechanics, nonlinear optics) from 2021 to 2025.