Low bend loss optical fiber with a germania doped core

A single mode optical fiber comprising:

• a germania doped silica central core region having outer radius r1 and 3.5 microns≤r1≤5.5 microns and refractive index Δ1, a maximum refractive index Δ1max, and 0.32%≤Δ1max≤0.45%, and a core alpha profile, Coreα where 1≤Coreα≤100;
• and
• a cladding region comprising (i) a first inner cladding region surrounding the germania doped silica central core region having an outer radius r2 and 4.5 microns≤r2≤7.5 microns and refractive index Δ2 and an r1/r2 ratio and 0.60≤r1/r2≤0.90;
• (ii) and a second inner cladding region surrounding the first inner cladding region having an outer radius r3 and 5.5 microns≤r3≤20.5 microns, comprising refractive index Δ3, and a maximum refractive index Δ3max and 0.02%≤Δ3max≤0.15%;
• and (iii) an outer cladding region surrounding the second inner cladding region and comprising refractive index Δ4, wherein Δ1max>Δ3max>Δ4≥Δ2;
• wherein the single mode optical fiber exhibits a 22 m cable cutoff less than or equal to 1260 nm, a macrobending loss at 1550 nm of ≤0.75 dB/turn on a 20 mm diameter mandrel, has a zero dispersion wavelength, λ0, of 1300 nm≤λ0≤1324 nm, and a mode field diameter at 1310 nm of 8.2 microns≤MDF1310nm≤9.6 microns.