Designing broad band dispersion compensation with square lattice PCF and applications to ASE suppression with ultra negative dispersion

This article deals with the broadband dispersion characteristic of the dual core square lattice Photonic crystal fiber. All the associated geometrical parameters are investigated toward designing broadband dispersion compensating devices for communications wavelength. The design establishes that for broadband dispersion compensation the effect of change of geometrical parameters is less significant. Our numerical analysis establishes that we could design a broadband dispersion of −2500 ps/nm/km which can compensate the dispersion some hundred times to the length of the inline fiber. The design also considers the dispersion slope and kappa values which matches well with the existing SMF-28. Thus our design will be very helpful for a practical purpose. Again applying the power transform from inner core to the outer core at the coupling wavelength for the ultra-negative dispersion, we have studied the design of a possible ASE suppressed amplifier where wavelengths after coupling wavelength can’t be amplified as most of the power goes to the outer core where erbium ions do not exist to be amplified. The principle will be extremely useful for future ASE suppressed amplifier study where we need to amplify only a particular range of wavelengths and suppress the other wavelengths.