Reflection from a free carrier front via an intraband indirect photonic transition
Abstract
The reflection of light from moving boundaries is of interest both fundamentally and for applications in frequency conversion, but typically requires high pump power. By using a dispersion-engineered silicon photonic crystal waveguide, we are able to achieve a propagating free carrier front with only a moderate on-chip peak power of 6 W in a 6 ps-long pump pulse. We employ an intraband indirect photonic transition of a co-propagating probe, whereby the probe practically escapes from the front in the forward direction. This forward reflection has up to 35% efficiency and it is accompanied by a strong frequency upshift, which significantly exceeds that expected from the refractive index change and which is a function of group velocity, waveguide dispersion and pump power. Pump, probe and shifted probe all are around 1.5 µm wavelength which opens new possibilities for “on-chip” frequency manipulation and all-optical switching in optical telecommunications.
Citation
Gaafar , M A , Jalas , D , O’Faolain , L , Li , J , Krauss , T F , Petrov , A Y & Eich , M 2018 , ' Reflection from a free carrier front via an intraband indirect photonic transition ' , Nature Communications , vol. 9 , 1447 . https://doi.org/10.1038/s41467-018-03862-0
Publication
Nature Communications
Status
Peer reviewed
ISSN
2041-1723Type
Journal article
Rights
© The Author(s) 2018. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
Description
M.A.G, D.J., A.Y.P. and M.E. acknowledge the support of the German Research Foundation under grant no. EI 391/13-2, and appreciate the support of CST, Darmstadt, Germany, with their Microwave Studio Software. M.A.G, D.J., A.Y.P. and M.E. acknowledge the support of Michel Castellanos Muñoz in preparing the grant proposal. J.L. acknowledges the supports of the Ministry of Science and Technology of China (2016YFA0301300) and National Natural Science Foundation of China (11761131001, 11674402). LOF acknowledges support form the Science Foundation Ireland under Grant SFI12/RC/2276.Collections
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