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Soliton Dynamics in Fiber Lasers: from Dissipative Soliton to Dissipative Soliton Resonance

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Soliton Dynamics in Fiber Lasers: from Dissipative Soliton to Dissipative Soliton Resonance Soliton dynamics in fiber lasers : from dissipative soliton to dissipative soliton resonance Georges Semaan To cite this version: Georges Semaan. Soliton dynamics in fiber lasers : from dissipative soliton to dissipative soliton resonance. Physics [physics]. Université d’Angers, 2017. English. NNT : 2017ANGE0029. tel- 01720431 HAL Id: tel-01720431 https://tel.archives-ouvertes.fr/tel-01720431 Submitted on 1 Mar 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Georges SEMAAN Mémoire présenté en vue de l’obtention du grade de Docteur de l'Université d'Angers sous le sceau de l’Université Bretagne Loire École doctorale: ED-3MPL Discipline: 30 – Milieux dilués et Optique Spécialité: Physique Unité de recherche: LphiA- EA 4464 Soutenue le 17-11-2017 Thèse N°: (10) Soliton dynamics in fiber lasers: From dissipative solitons to dissipative soliton resonance JURY Rapporteurs : M. Guy Millot, Professeur, Université de Bourgogne M. Pascal Besnard, Professeur, Université de Rennes I Examinateurs : M. Benoit Boulanger, Professeur, Université de Grenoble M. Andrey Komarov, Docteur ès Sciences, Université de Novosibirsk Directeur de Thèse : M. François Sanchez, Professeur, Université d’Angers Co-encadrant de Thèse : M. Mohamed Salhi, MCF, Université d’Angers “Τα άτομα και το κενό είναι η αρχή των πάντων και τα υπόλοιπα είναι κατασκευάσματα του νου” "Nothing exists except atoms and empty space, everything else is just opinion" Democritus To my wife, Χριστίνα Acknowledgements The last 3 years during which I was enrolled as a PhD student and working at the Laboratoire de Photonique d’Angers were a blast. Scientifically speaking, I ex- plored new aspects of physics especially in optics, that I was never exposed to before. On a social scale, this adventure allowed to meet new people with different perspec- tives and to have new friends; friends to keep. This whole combination of circum- stances forged me with broader skills at distinct levels and I grew into what I believe to be a plump scientist. It had been a great learning and a challenging experience which I would not be able to achieve without being well surrounded and wisely advised dur- ing my studies. Therefore, I would like to express my deepest gratitude to the people who helped and participated in the fulfillment of this thesis. Firstly, I would like to express my sincere gratitude to my main advisor Prof. François Sanchez for his continuous support, patience, motivation, sense of humor and immense encyclopedic knowledge of the matter. His guidance helped me during my research and writing of this thesis, and his tips and tricks arouse in me a deep sense of curiosity I did not have before. I could not have imagined having a better advisor and mentor for my Ph.D. study, and a better person when needed the most. I am also thankful to Dr. Mohamed Salhi my second advisor. He supported this work, advised me on experimental and theoretical issues and provided all the help needed when problems occurred. I would like to thank him for the various discussions we had in the office we shared, no matter what the subject was. Being an easy-going person, he made me feel comfortable in tackling the issues I was facing, knowing that I would rely on his expertise. Besides my advisors, I would like to thank the rest of my thesis committee: Prof. Guy Millot, Prof. Pascal Besnard, Prof. Benoit Boulanger and Dr. Andrey Komarov, for their insightful comments and remarks which incented me to widen my research from various perspectives. Dr. Andrey Komarov represents a very important part of this thesis. He helped in the numerical and analytical assessments and has offered his experience and knowledge to make my experiments more complete. i My sincere thanks also go to Dr. Alioune Niang, who helped me from the very first days in understanding the subject and the instruments and provided with all the information needed to succeed. He has been a good friend and without his precious support, it would not be possible to conduct this research. My deepest gratitude goes to the technical team at the Physics Department (Christophe Cassagne, Leo Monnereau, Alain Mahot, Dominique Guichaoua, and Christian Auguste). They provided all the help and effort needed for the success of this research. I thank my fellow lab mates for the stimulating discussions and for all the fun we had in the last three years. Special dedications to Dr. Valentin Besse who was my first officemate, Dr. Julien Merigeon with whom we reviewed the history of France and the social problems in our community, Dr. Ariadni Kerasidou one of my closest friends who knew how to make the days go smoother, Dr. Khmaies Guesmi, PhD stu- dent Fatma Ben Braham and Paul Mouchel who provided technical expertise and dif- ferent components used in this research. Also, I thank Prof. Zhi Chao Luo for the op- tical tapers from China. I may not remember everyone but know that you have collab- orated to the success of this thesis in your own way. I am indebted to my family for all the sacrifices they had to do and for their continuous and unconditional support. Thank you so much. Finally, I would like to thank my wife for having faith in me, supporting me and proving me that I am always wrong when it comes to general discussions. ii Table of contents Acknowledgements ............................................................................................................................................................... ii List of Figures.......................................................................................................................................................................... v Abbreviations......................................................................................................................................................................... ix Introduction .................................................................................................................................................... 1 1.1 A historical background ................................................................................................................................ 1 1.2 Motivation ....................................................................................................................................................... 4 1.3 Thesis outline .................................................................................................................................................. 6 The physics of fiber lasers ........................................................................................................................... 9 2.1 Optical fibers ................................................................................................................................................... 9 2.1.1 Basics of electromagnetic waves .................................................................................................... 10 2.1.2 Principle of waveguiding ................................................................................................................ 10 2.1.3 Rare-earth doped fibers ................................................................................................................... 12 2.2 Pulse propagation in optical fibers ............................................................................................................. 13 2.2.1 Absorption ........................................................................................................................................ 14 2.2.2 Dispersion ......................................................................................................................................... 14 2.2.3 Nonlinear effects .............................................................................................................................. 16 2.3 The fundamentals of mode-locking ........................................................................................................... 21 2.3.1 Introduction to mode-locked fiber lasers ...................................................................................... 21 2.3.2 Pulsed regimes ................................................................................................................................. 23 2.3.3 Techniques of mode-locking........................................................................................................... 26 2.4 Chapter summary ......................................................................................................................................... 30 External injection effects in mode-locked lasers: a study of stability ................................................ 31 3.1 Brief introduction to external injection ...................................................................................................... 31 3.2 Fiber ring cavity schematic with an auxiliary laser setup ....................................................................... 33 3.3 Influence of an external laser injection on
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