Chi(3) telecom-wavelength nonlinear optics in silicon-based waveguide circuits

Research Area: Integrated nonlinear optics , Silicon photonics for telecom, datacom and interconnect

Main Researcher: Francois Leo

Nonlinear silicon photonics is drawing a lot of interest because of its potential applications in telecommunications and spectroscopy. Due to the intrisically high nonlinear index of silicon and the high confinement offered by the silicon-on-insulator platform, nonlinear parameters 5 orders of magnitude higher than that of standard optical fibers have been reported. However, the telecom band lies above half the band gap of silicon such that two photon absorption (TPA) is relatively high. However, due to the slow recombination time in silicon (1 ns), it is the subsequent free carrier absorption (FCA) that is really detrimental to the observation of most nonlinear effects. We are currently investigating how to circumvent this problem. The main three directions are moving to new materials, compatible with the silicon platform, remove the carriers electrically or the use of short pulses so FCA becomes negligible.

SEM cross section and color-map of the mode distribution in a silicon on insulator waveguide. From X. Liu, R. M. Osgood, Y. A. Vlasov, and W. M. J. Green, Nature Photonics 4, 557 (2010).

Our main focus has been on the use of hydrogenated amorphous silicon waveguides. The band gap of such waveguides was measured to be 1.6 eV (crystalline silicon has a band gap of 1.12 eV), which corresponds to a wavelength of 1550 nm for the TPA threshold. This resulted in the demonstration of 26.5 dB amplification at telecom wavelengths. However a degradation of the material under high optical powers was observed, due to the recombination of carriers (known as the Staebler-Wronski effect). However it is possible to carbon-dope the a-Si in order to increase the band gap and hence reduce the TPA. Another possibility is to move to other materials, such as large band gap III-V semiconductors that can be integrated on the silicon platform (e.g. through bonding) and possess similarly high third order nonlinearities. Working with short pulses is another way of avoiding FCA. It was predicted by simulations that supercontinuum generation through soliton fission is possible at telecom wavelength. Finally, as it is not the TPA but rather the FCA that kills the performance, it was demonstrated that CW nonlinear effects could be observed by removing carriers through the integration of a reverse biased PIN junction.

Other people involved:

• Francois Leo
• Pijush Kumar Pal
• Utsav Dave
• Bart Kuyken
• Roel Baets
• Raphael Van Laer

Related Research Projects

• EOS: Pulse (Pattern Formation in Integrated Lasers for Spectroscopy and Terahertz Wave Generation)

Downloads

Characterization of graphene-covered SiN waveguide using four-wave mixing

PhD thesises

• Raphael Van Laer, Interactie tussen licht en geluid in nanoschaal siliciumgolfgeleiders, Light-Sound Interaction in Nanoscale Silicon Waveguides, (5/2016)  
• Koen Alexander, Geintegreerde siliciumnitridefotonica met sterk niet-lineaire dunne films en 2D-materialen: eigenschappen en componenten, Integrated Silicon Nitride Photonics with Highly Nonlinear Thin Films and 2D Materials: Properties and Devices, (12/2018)  
• Utsav Dave, Niet-lineaire optica in golfgeleidercircuits geimplementeerd in a-Si:H-op-isolator en InGaP-op-isolator, Nonlinear Optics in a-Si:H-on-Insulator and InGaP-on-Insulator Waveguide Circuits, (1/2017)  

Publications

International Journals


1. B. Kuyken, M. Billet, F. Leo, Y. Kresten, M. Pu, Octave-spanning coherent supercontinuum generation in an AlGaAs-on-insulator waveguide, Optics Letters, 45(3), p.603-606 doi:10.1364/OL.45.000603 (2020)  .
2. K. Alexander, N.A. Savostianova, S.A. Mikhailov, D. Van Thourhout, B. Kuyken, Gate-Tunable Nonlinear Refraction and Absorption in Graphene-Covered Silicon Nitride Waveguides, ACS Photonics, 5(12), p.4944-4950 doi:10.1021/acsphotonics.8b01132 (2018).
3. U.D. Dave, C. Ciret, S.-P. Gorza, S. Combrie, A. De Rossi, F. Raineri, G. Roelkens, B. Kuyken, Dispersive wave based octave spanning super continuum generation in InGaP membrane waveguides on a silicon substrate, Optics Letters, 40(15), p.3584 doi:10.1364/OL.40.003584 (2015)  .
4. A. Subramanian, E.M.P. Ryckeboer, A. Dhakal, F. Peyskens, A. Malik, B. Kuyken, H. Zhao, S. Pathak, A. Ruocco, A. De Groote, P.C. Wuytens, D. Martens, F. Leo, W. Xie, U.D. Dave, M. Muneeb, Pol Van Dorpe, J. Van Campenhout, W. Bogaerts, P. Bienstman, N. Le Thomas, D. Van Thourhout, Zeger Hens, G. Roelkens, R. Baets, Silicon and silicon nitride photonic circuits for spectroscopic sensing on-a-chip , Photonics Research (invited), 5(3), p.B47 doi:10.1364/PRJ.3.000B47 (2015)  .
5. U.D. Dave, B. Kuyken, F. Leo, S.P. Gorza, S. Combrie, A. De Rossi, F. Raineri, G. Roelkens, Nonlinear properties of dispersion engineered InGaP photonic wire waveguides in the telecommunication wavelength range, Optics Express, 23(4), p.4650 doi:10.1364/OE.23.004650 (2015)  .
6. F. Leo, S.P. Gorza, S.Coen, B. Kuyken, G. Roelkens, Coherent supercontinuum generation in a silicon photonic wire in the telecommunication wavelength range, Optics Letters, 40(1), p.123-126 doi:10.1364/ol.40.000123 (2015)  .
7. F. Leo, J. Safioui, B. Kuyken, G. Roelkens, S.P. Gorza, Generation of coherent supercontinuum in a-Si:H waveguides: experiment and modeling based on measured dispersion profile, Optics Express, 22(23), p.28997-29007 doi:10.1364/oe.22.028997 (2014)  .
8. F. Leo, S-P. Gorza, J.Safioui, P. Kockaert, S. Coen, U.D. Dave, B. Kuyken, G. Roelkens, Dispersive wave emission and supercontinuum generation in a silicon wire waveguide pumped around the 1550 nm telecommunication wavelength, Optics letters, 39(12), p.3623 doi:10.1364/OL.39.003623 (2014).
9. J. Safioui, F. Leo, B. Kuyken, S. Selvaraja, R. Baets, P. Emplit, G. Roelkens, S. Massar, Supercontinuum generation in hydrogenated amorphous silicon waveguides at telecommunication wavelengths, Optics Express, 22(3), p.3089-3089 doi:10.1364/oe.22.003089 (2014)  .

International Conferences


1. M. Al Mahmoud, S. Clemmen, Design of Silicon-Based Quantum Squeezer, The 25th European Conference on Integrated Optics, 402(2024), Germany, p.383 doi:https://doi.org/10.1007/978-3-031-63378-2_63 (2024).
2. L. Reis, M. Billet, F. Raineri, I. Sagnes, K. Pantzas, G. Beaudoin, G. Roelkens, F. Leo, B. Kuyken, Octave-spanning coherent supercontinuum generation in a GaP-on-insulator waveguide, SPIE Photonics West 2024, PC12869, United States, p.PC128690J doi:10.1117/12.3002440 (2024).
3. L. Reis, M. Billet, T. Vandekerckhove, F. Raineri, I. Sagnes, K. Pantzas, G. Beaudoin, G. Roelkens, F. Leo, B. Kuyken, Large size gallium phosphide micro-transfer printing for integrated nonlinear photonics, Frontiers in Optics + Laser Science 2023 (FiO/LS), United States, p.paper FTh3E.6 (2 pages) doi:10.1364/FIO.2023.FTh3E.6 (2023)  .
4. J. Zhang, L. Bogaert, M. Billet, D. Wang, B. Pan, S. Qin, E. Soltanian, S. Cuyvers, D. Maes, T. Vanackere, T. Vandekerckhove, S. Poelman, M. Kiewiet, I. Luntadila Lufungula, X. Guo, H. Li, J. De Witte, G. Lepage, P. Verheyen, J. Van Campenhout, B. Kuyken, G. Morthier, D. Van Thourhout, R. Baets, G. Roelkens, Photonic integrated circuits realized using micro-transfer printing, PIERS (invited), (2023).
5. M. Pu, Y. Liu, C. Kim, Y. Zheng, E. Semenova, D. Kong, Hao Hu, Michael Galili, L. Katsuo Oxenlowe, B. Kuyken, M. Billet, F. Leo, Kresten Yvind, Broadband optical signal processing in AlGaAs-on insulator waveguides, OSA Advanced Photonics Congress (invited), doi:10.1364/IPRSN.2020.ITu2A.1 (2020).
6. K. Alexander, B. Kuyken, D. Van Thourhout, Electrically Tunable Nonlinear Refraction and Absorption in Graphene-covered SiN Waveguides, CLEO 2018, United States, doi:10.1364/CLEO_QELS.2018.FF2E.3 (2018)  .
7. K. Alexander, M. Mohsin, U.D. Dave, L. Abdollahi Shiramin, S. Clemmen, D. Neumaier, B. Kuyken, D. Van Thourhout, Electrically Tunable Optical Nonlinearity of Graphene-covered SiN waveguides, Conference on Lasers and Electro-Optics (CLEO) 2017, United States, p.paper FM2F.3 doi:10.1364/cleo_qels.2017.fm2f.3 (2017)  .
8. K. Alexander, B. Kuyken, D. Van Thourhout, Characterization of graphene-covered SiN waveguide using four-wave mixing, Annual Symposium of the IEEE Photonics Benelux Chapter, Belgium, (2016)  .
9. U.D. Dave, B. Kuyken, Sylvain Combrie, Alfredo De Rossi, Fabrice Raineri, G. Roelkens, Octave spanning supercontinuum generation in InGaP waveguides on a silicon substrate at 1550 nm, Integrated Photonics Research, Silicon and Nano Photonics (IPR 2015), United States, p.paper IM4B.5 doi:10.1364/iprsn.2015.im4b.5 (2015)  .

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