Efficient Kerr soliton comb generation in micro-resonator with interferometric back-coupling

Year: 2022

Authors: Boggio J.M.C.; Bodenmuller D.; Ahmed S.; Wabnitz S.; Modotto D.; Hansson T.

Autors Affiliation: innoFSPEC-Leibniz Institut f

Abstract: Nonlinear Kerr micro-resonators have enabled fundamental breakthroughs in the understanding of dissipative solitons, as well as in their application to optical frequency comb generation. However, the conversion efficiency of the pump power into a soliton frequency comb typically remains below a few percent. We fabricate and characterize a hybrid Mach-Zehnder ring resonator geometry, consisting of a micro-ring resonator embedded in an additional cavity with twice the optical path length of the ring. The resulting interferometric back coupling enables to achieve an unprecedented control of the pump depletion: pump-to-frequency comb conversion efficiencies of up to 55% of the input pump power is experimentally demonstrated with a soliton crystal comb. We assess the robustness of the proposed on-chip geometry by generating a large variety of dissipative Kerr soliton combs, which require a lower amount of pump power to be accessed, when compared with an isolated micro-ring resonator with identical parameters. Micro-resonators with feedback enable accessing new regimes of coherent soliton comb generation, and are well suited for comb applications in astronomy, spectroscopy and telecommunications. Increasing the conversion efficiency of soliton crystals will enable further application of optical frequency comb. Here the authors engineer an hybrid Mach-Zehnder micro-ring resonator to achieve 80% pump-to-comb conversion efficiency based on dissipative Kerr solitons.

Journal/Review: NATURE COMMUNICATIONS

Volume: 13 (1)      Pages from: 1292-1  to: 1292-11

More Information: This work was supported by the BMBF (Federal Ministry of Education and Research) through grants 03Z2AN11 and 03Z2AN12. The work of S.W. was supported by the European Research Council (ERC) under the European Union´s Horizon 2020 research and innovation program (grant no. 740355 and grant no. 874596). T.H. acknowledges funding from the Swedish Research Council (Vetenskapsradet, grant no. 2017-05309). Fruitful discussions with M. Ujevic and K. Krupa are gratefully acknowledged.
KeyWords: frequency combs; supercontinuum generation; nonlinear dynamics; laser; silicon
DOI: 10.1038/s41467-022-28927-z