Silica-based Highly Nonlinear Fibers and Their Applications

Masaaki Hirano
Sumitomo Electric Industries, ltd.

Wednesday, June 16, 2010 at 4:00pm
Engr IV Maxwell Room 57-124

Abstract
Nonlinear effects are easily generated through an optical fiber due to the tight confinement of optical power into the small core area and the long interaction length between the glass and the optical field. In transmission fibers, nonlinearities should be suppressed because they severely limit entire information capacity of optical communication systems. On the other hand, fiber nonlinearities have been positively utilized for applications including optical amplifiers and all-optical signal processing, promising devices for near-future high capacity networks. In order to be practically applied to such devices, optical fibers mush have enhanced nonlinearities and hence silica-based highly nonlinear fiber (HNLF) has been developed; its nonlinear coefficient is enhanced as much as 30/W/km, 20-times higher than that of a standard single mode fiber.

This seminar will present recent progresses on HNLFs and their applications. One of the key issues for HNLFs is appropriate design of chromatic dispersion characteristics. We will demonstrate HNLF having extremely uniform zero-dispersion wavelength of +/-1nm along with 3-km long fiber, which means that the core radius fluctuates only +/-1.2nm. We will also present fabrication results of the forth-order dispersion controlled HNLFs. Additionally, applications utilizing fabricated HNLF, including broadband and selective wavelength conversion based on Four-wave-mixing process, supercontinuum generation and Raman amplification, will be demonstrated.

Biography
Mr. Masaaki Hirano received the B.S. and the M.S. degree in chemistry from Keio University, Tokyo, Japan, in 1995 and 1997, respectively. In 1997, he joined Sumitomo Electric Industries, Ltd., Yokohama, Japan. He is now with Optical Communications R&D Laboratories, and has been involved in design, fabrication and evaluation of advanced optical fibers, such as low loss and low nonlinear pure silica core fibers, low insertion loss dispersion compensating fibers, and highly nonlinear fibers.