Since only a small fraction of the light propagates in glass, the effect of material nonlinearities is significantly reduced and the fibers do not suffer from the same limitations on loss as conventional fibers made from solid material alone.
While hollow core PCF holds the promise to become the next generation ultra-low loss transmission fiber, it already finds
Hollow core fibers for 1550 nm wavelength are now available with two different core sizes, formed by removing either 7 cells (HC-1550-02) or 19 cells (HC19-1550-01) from the cladding.
The larger core fibers offer lower loss, lower dispersion and higher breakdown threshold, while the smaller core fibers provide a wider uninterrupted operating wavelength band and support a smaller number of modes.
・>97% of optical power located in air
・Quasi-Gaussian fundamental mode
・Can be filled with gas
・Low bend loss down to few mm bend radius
・Fresnel reflection to air at the end faces <10e-4
・Around 65% of fiber cross section composed of solid silica, facilitating fusion splicing to conventional fibers