Single-mode fiber with low dispersion slope

An optical fiber, comprising:

• a central core region having an outer radius r1 of 3 μm to 5.5 μm, and a maximum refractive index Δ1 of 0.25% to 0.5% and an alpha (α) profile of 1 to 20;
• and
• a cladding region comprising (i) a first inner cladding region surrounding the central core, having a refractive index Δ2 of −0.25% to 0.05% and a radius r2 of 6 μm to 12 μm, (ii) a second inner cladding region, surrounding the first inner cladding region, having a refractive index Δ3 of 0.02% to 0.2% and a radius r3 of 7 μm to 15 μm, and (iii) an outer cladding region, surrounding the second inner cladding region, having a refractive index Δ4 between −0.05% to 0.1%;
• wherein the optical fiber exhibits a cable cutoff of less than 1260 nm, mode field diameter at 1310 nm of greater than 8.2 microns, a zero dispersion wavelength between 1300 nm and 1324 nm and a chromatic dispersion slope at 1310 nm of less than or equal to 0.083 ps/nm2/km.

An optical fiber, comprising:

• a central core region having an outer radius r1 of 3 μm to 5.5 μm, and a maximum refractive index Δ1 of 0.25% to 0.5% and an alpha (α) profile of 1 to 20;
• and
• a cladding region comprising (i) a first inner cladding region surrounding the central core, having a refractive index Δ2 of −0.25% to 0.05% and a radius r2 of 6 μm to 12 μm, (ii) a second inner cladding region, surrounding the first inner cladding region, having a refractive index Δ3 of 0.02% to 0.2% and a radius r3 of 7 μm to 15 μm, and (iii) an outer cladding region, surrounding the second inner cladding region, having a refractive index Δ4 between −0.05% to 0.1%;
• wherein the optical fiber exhibits a cable cutoff of less than 1260 nm, a mode field diameter at 1310 nm of greater than 8.2 microns, a zero dispersion wavelength of less than 1400 nm and a chromatic dispersion slope at 1310 nm of less than or equal to 0.075 ps/nm2/km.