Feroza BEGUM, Yoshinori NAMIHIRA, S. M. ABDUR RAZZAK, Shubi KAIJAGE, Kazuya MIYAGI, Nguyen Hoang HAI, and Nianyu ZOU

Graduate School of Engineering and Science, University of the Ryukyus, Okinawa 903-0213, Japan

(Received November 22, 2006; Accepted March 15, 2007)

A new simple structure of an index-guiding highly nonlinear dispersion-flattened square photonic crystal fiber (HNDF-SPCF) with low confinement losses is proposed. The results reveal that it is possible to design five-rings HNDF-SPCFs with a flattened dispersion of 0.43 ps/(nm·km), low dispersion slope of −0.02 ps/(nm²·km), low confinement loss of approximately 10⁻³ dB/m, and a large nonlinear coefficient of approximately 35 W⁻¹ km⁻¹ at 1.55 μm. It is also observed that the confinement loss is less than 10⁻¹ dB/m in the wavelength range of 1.2–1.7 μm.

Key words: fiber characterization, nonlinear coefficient, chromatic dispersion, confinement loss