Dispersion ultrastrong compensating fiber based on a liquid-filled hybrid structure of dual-concentric core and depressed-clad photonic crystal fiber

Abstract

To achieve a dispersion-compensation photonic crystal fiber with an ultralarge negative chromatic dispersion coefficient, this paper theoretically investigates a liquid-filled hybrid structure of dual-concentric core photonic crystal fiber (DCC-PCF) and depressed-clad photonic crystal fiber (DeC-PCF). The proposed hybrid structure reveals an important property: The design can avoid the restriction of “mutual involvement” between two supermodes, thereby significantly increasing the index slope difference between two supermodes. Ultimately, the negative chromatic dispersion coefficient is greatly enlarged. The numeric results indicate that the negative chromatic dispersion coefficient for the proposed hybrid dispersion-compensating PCFs is up to −40400  ps/(km−nm) at a wavelength of around 1.55 μm, which is approximately 1.81 times larger than that of the previous structure.