Custom Bragg grating and Application Progress

   Gu  Xijia
Department of Electrical and Computer Engineering, Ryerson University
350 Victoria St., Toronto, Ontario, Canada

Time & Date：13:30 , Jun, 19, 2012
Place: Room B415 ,  computer Center Building

Abstract
 
In this seminar, our recent research progress in the development of special fiber Bragg gratings (FBGs) and their applications will be presented. Particularly four types of FBG design and applications will be discussed, namely, a) FBGs fabricated on large-mode area fiber such as 20/400 μm core/cladding fiber for high power Yb-doped fiber lasers. b) Grating pairs on polarization maintain (PM) fiber for single-polarization fiber lasers. Using such a pair of FBG as the laser cavity to select both wavelength and polarization, a high extinction ratio of over 25 dB has been achieved. c)  FBGs for dual wavelength fiber laser for mid-IR laser emission. With two FBG pairs made, dual wavelength emissions with a Er/Yb-doped fiber as gain medium at 1058.8 and 1554.4 nm, respectively were generated. The laser was applied successfully for differential frequency generation (DFG) by pumping a PPLN crystal to generate mid-IR emission at 3.27 μm. d) FBG-based FP cavity for acoustic sensors. High fineness FP cavity was made on SMF-28 fiber that generated a center fringe with a linewidth of 0.2 pm and an isolation of large than 45 dB. The FBG FP has been used as a musical instrumental pickup, or a photonics guitar.
 
Biography of Speaker

Xijia Gureceived his B.Sc. degree from Nankai University in Tianjin, China, in 1982; a M.Sc. degree from University of Toronto in Toronto, Ontario, Canada, in 1984; and a Ph.D. degree from University of Waterloo in Waterloo, Ontario, Canada, in Aug.1987. He worked as a Research Fellow in Max-Planck-Institute fuer Stromungsforschung in Goettingen, German from Sept. 1987 to Feb. 1989, and in University of Toronto from March 1989 to Oct. 1990. After that, he joined Photonics Research Ontario, six years as a Staff Scientist and three years as a Manager, involved in many research projects related to lasers and laser applications. In Nov. 1999, he joined JDS Uniphase as a Senior Manager, developed many fiber products for telecommunication such as: fiber grating filters, DWDM modules, and tunable filters.
 
In 2003, he joined Department of Electrical and Computer Engineering, Ryerson University in Toronto, Ontario, Canada. He has published 67 referred journal articles, 31 conference papers, and holds four patents. His current research includes high-power fiber lasers, fiber-optic devices and modules and fiber-optic sensors.