High Power Fiber Sources
강   사   Prof. Johan Nilsson
소   속   Optoelectronic Research Centre, University of Southampton, Southampton, UK
시   간   2008년 5월 13일 (화요일) 11:00 - 12:00
장   소   제1 신공학관 301동 1112호

Abstract
The huge investment made by the telecommunications community in advancing photonics over the last three decades brings a considerable opportunity to disrupt other areas with new optical technology. The extraordinary level of optical control coupled with the extended reliability and small size that is routine in telecoms is regarded as revolutionary in, for example, lasers for industrial processing or the life sciences. Remarkably, through cladding-pumping of ytterbium-doped silica fibers, the milliwatts of optical amplifiers for telecommunication can be scaled with near-perfect beam quality to several kilowatts of power with largely the same technology. Furthermore, beyond raw power, fibers offer advantages such as control, efficiency, manufacturability, and reliability. These derive from the fundamental fiber geometry, as well as advances in fiber design, fabrication, and pump diodes, largely driven by the optical communications industry.
Unique among high power lasers, fiber sources can be monolithic; the light being confined to the core of a fiber. This gives immunity to thermal distortion of the beam, almost instant start-up, very high stability, and resistance to the environment. Maintenance is minimal, with no need for realignment or cleaning of components. With small size, maintenance-free operation, high thermal and electrical efficiency, and exceptional control with outstanding (diffraction-limited) beam quality, high power fiber sources has the potential to change every industry and discipline it encounters. It challenges currently held views on how to make things, how to repair things, and how to destroy things. We will review recent progress in a range of operating regimes, current research directions, and the underlying science and technology.

강사이력

Johan Nilsson is a Professor at the Optoelectronics Research Centre (ORC), University of Southampton, England. In 1994, he received a doctorate in Engineering Science from the Royal Institute of Technology, Stockholm, Sweden, for research on optical amplification. Since then, he has worked on optical amplifiers and amplification in lightwave systems, optical communications, and guided-wave lasers, first at Samsung Electronics and later at the ORC. His research has covered system, fabrication, and materials aspects of guided-wave lasers and amplifiers, and in particular device aspects of high power fiber lasers and erbium-doped fiber amplifiers. He is leading ORC’s high-power fiber laser group which, in recent years, demonstrated a number of world-firsts and world-records in the field, including the first single-mode kW fiber laser, the first cladding-pumped fiber Raman laser, and a diffraction-limited single-frequency linearly polarized Yb-doped fiber source with over 0.4 kW of output power. He has published nearly 300 scientific articles, including patents as well as post-deadline, plenary, key-note, invited and tutorial papers at leading international conferences. He has also taught fiber laser short courses at Photonics West and OFC. He is a member of the Optical Society of America and a consultant to Southampton Photonics, which he co-founded. He is serving on the technical program committee of Frontier in Optics (formerly OSA annual meeting) and Advanced Solid State Photonics topical meeting. He has also been a member of the technical program committee of the Optical Amplifiers and their Applications topical meeting, the Optical Fiber Communication conference (OFC), and the Fiber Laser Systems Technology and Applications conference at Photonics West, which he chaired in 2006. He is also the chair of the Laser Science and Engineering technical group in OSA’s Science and Engineering Council.