An optical transmission fiber has a refractive index profile with an area of
increased
index of refraction at the inner core of the fiber, an annular region positioned
radially outward from the inner core with an index of refraction exceeding the
index of the inner core, and at least a low dopant content region in a cross-sectional
region between the inner core and the annular region. A low loss cladding layer
surrounds the core region. The optical transmission fiber with this segmented core
profile provides a high effective area, low non-linearity coefficient, nonzero
dispersion, and relatively flat dispersion slope.
