Abstract: Nonlinear effects in optical fibers impose different limitations on the communications link, and an understanding of such effects is almost a prerequisite for actual lightwave-system designers. On the other hand, they offer a variety of possibilities for all-optical signal processing, amplification and regeneration. The nonlinear effects are enhanced dramatically and new phenomena are observed in the so called photonic crystal fibers. In this talk we review the effects – both detrimental and potentially beneficial – of optical nonlinearities in conventional and in photonic crystal fibers.

Brief Biography of the Speaker:
Mario F. S. Ferreira was born in Ovar, Portugal. He graduated in Physics from the University of Porto, Portugal, in 1984. Since then, he became an assistant lecturer, first at the Mathematics Department and afterwards at the Physics Department of the University of Aveiro, Portugal, from which institution he received the Ph.D. degree in Physics in 1992. He is now a Professor at the same Physics Department.
Between 1990 and 1991 he was at the University of Essex, UK, performing experimental work on external cavity semiconductor lasers and nonlinear optical fiber amplifiers. His research interests have been concerned with the modeling and characterization of multi-section semiconductor lasers for coherent systems, quantum well lasers, optical fiber amplifiers and lasers, soliton propagation, polarization and nonlinear effects in optical fibers. He is actually the leader of the Optics and Optoelectronics Group of the I3N – Institute of Nanostructures, Nanomodelling and Nanofabrication. He has written more than 200 scientific journal and conference publications, a book with the title: "Optics and Photonics" (Lidel, 2003, in Portuguese) and another with the title: "Nonlinear Effects in Optical Fibers" (John Wiley & Sons, to appear in August 20010).
He is a member of the Optical Society of America (OSA), SPIE - The International Society for Optical Engineering, The New York Academy of Sciences (NYAS), the American Association for the Advancement of Science (AAAS), the European Optical Society (EOS), the European Physical Society (EPS) and the Portuguese Physical Society.
He served in various committees of the Optical Society of America (OSA) and of SPIE – The International Society for Optics and Photonics, having been also a member of the Telecommunications Committee of the "International Association of Science and Technology for Development" (IASTED). He is a Visiting Lecturer of SPIE – The International Society for Optics and Photonics. He served in the technical committees of various international conferences, being actually one of the Chairs of the Conference "Optical Sensors", which is part of the Symposium "Advanced Photonics: OSA Optics & Photonics Congress", to be held at Karlsruhe, Germany, 21-24 June 2010.
He served as a reviewer of several scientific journals in the area of optics and optoelectronics. He is presently an Associate Editor of "Optical Fiber Technology- Materials, Devices, and Systems" (Elsevier) and a member of the Advisory Board of "Fiber and Integrated Optics" (Taylor & Francis), "Nonlinear Optics, Quantum Optics" (Old City Publishing, Inc.), "Research Letters in Optics" (Hindawi Publishing Corporation), and "International Journal of Optics" (Hindawi Publishing Corporation). He was the Guest Editor of a Special Issue of "Fiber and Integrated Optics", published in 2005, dedicated exclusively to the fiber and integrated optics activity carried out in Portugal.