J. Eur. Opt. Society-Rapid Publ. 2025, 21, 23 Ó The Author( s), published by EDP Sciences, 2025 https:// doi. org / 10.1051 / jeos / 2025018 Available online at: https:// jeos. edpsciences. org
EOSAM 2024 Guest editors: Luca De Stefano and Raffaele Velotta
Journal of the European Optical Society-Rapid Publications
RESEARCH ARTICLE
Interplay of v( 2) and v( 3) effects for microcomb generation
Francesco Rinaldo Talenti 1, 2,*
, Luca Lovisolo 1, 2, Andrea Gerini 2, Huanfa Peng 3, Pedro Parra-Rivas 4, Tobias Hansson 5, Yifan Sun 6, Carlos Alonso-Ramos 1, Martina Morassi 1, Aristide Lemaître 1, Abdelmounaim Harouri 1, Christian Koos 3, Stefan Wabnitz 7, 8, Laurent Vivien 1, and Giuseppe Leo 2
1 |
Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120 Palaiseau, France |
2 |
Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Cité, 75013 Paris, France |
3 |
Institute of Photonics and Quantum Electronics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany |
4 |
Department of Chemistry and Physics, University of Almeria, 04120 Almeria, Spain |
5 |
Department of Physics, Chemistry and Biology, Linköping University, Linköping, SE-581 83, Sweden |
6 |
Service OPERA-Photonique, Université libre de Bruxelles, B-1050 Brussels, Belgium |
7 |
Dipartimento di ingegneria elettronica e telecomunicazioni, Sapienza University of Rome, 00184 Roma, Italy |
8 |
CNR-INO, Istituto Nazionale di Ottica, 80078 Pozzuoli, Italy |
Received 29 January 2025 / Accepted 7 April 2025
Abstract. While frequency comb generation in passive nonlinear optical cavities has been demonstrated in purely quadratic and Kerr platforms, the interplay between v ð2Þ and v( 3) effects is yet to be fully understood. In this work, we propose a doubly resonant AlGaAs microring design for second-harmonic Kerr-comb generation. We compute the full dispersion profile of the guided modes to describe the resulting dynamics. The doubly resonant condition implies the use of a double envelope mean-field model, and the confined field owns spectral components around both the pump and second harmonic wavelengths. The fabrication of such devices is discussed, and preliminary experimental results are presented. Due to its record nonlinear performance, we address AlGaAs as a promising platform for the generation of such novel microcomb sources.
Keywords: Optical frequency combs, Second harmonic generation, Nonlinear optics, AlGaAs.
1 Introduction
Optical frequency comb( OFC) generation based on secondharmonic( SH) nonlinear frequency conversion was first demonstrated in a bow-tie optical cavity [ 1, 2 ], and a cascade of v( 2) processes was found to mimic a Kerr effect resulting in a modulation-instability( MI) OFC regime [ 3 ]. Besides, Kerr whispering-gallery-mode resonators with a toroidal shape have been used to generate octave-spanning microcombs [ 4 ] and temporal cavity solitons( CSs) [ 5 ], as predicted a couple of decades earlier [ 6 ].
Today, novel architectures have been demonstrated to excite robust CSs dynamical attractors [ 7 ], while innovative pumping schemes, such as chirped-pulse pumping, have been proposed to achieve complete control on the CS dynamics [ 8 ]. In the same context, on-chip integration of quadratic platforms at the lm-size scale is receiving increasing attention with a view to possibly achieving lower-powerpumpthresholds [ 9 ]. This is witnessed by the recent records of v( 2) microring optical parametric oscillator( OPO) [ 10 ], Pockels micro-comb [ 11 ], and bicolor CSs [ 12 ].
At the same time, III-V semiconductors have proven interesting for nonlinear optical applications due to their energy bandgap tunability, which provides direct solutions for waveguide-dispersion engineering, and their typically high second- and third-order nonlinear response. As such, they led to paradigmatic demonstrations: SH vortex generation [ 13 ] and spin-orbit coupling [ 14 ] using nonlinear metasurfaces, entangled-photon sources [ 15, 16 ], ultralow-power Kerr OFC [ 17, 18 ], and photonic crystal cavity( PhC) OPO [ 19, 20 ]. Moreover, second harmonic generation( SHG) has been reported for( Al) GaAs [ 21 – 23 ] and( In) GaP alloys in both type I [ 24, 25 ] and type II [ 16, 26, 27 ] phase-matching( PM) schemes. Further perspective examples are broadband SHG [ 28 ] and electrically injected OPO [ 29 ].
Here, to model the OFC generation in a SHG-Kerr cavity [ 30, 31 ], we consider a double-envelope mean-field model, as was previously done to describe e. g. the field evolution of SHG [ 32, 33 ] and third-harmonic generation( THG) [ 34 ] in doubly resonant cavities. With this approach, one can predict Kerr-induced MI [ 35 ] and bistable soliton solutions [ 36 ] in a waveguide configuration. The case of an
* Corresponding author: francesco-rinaldo. talenti @ universite-paris-saclay. fr
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