In one embodiment, an optical fiber includes a first layer having a first refractive index and a second layer surrounding the first layer, where the second layer has a second refractive index, an inner radius, and an outer radius. The optical fiber also includes a third layer surrounding the second layer, where the third layer has a third refractive index, where the first refractive index is less than the second refractive index, where the third refractive index is less than the second refractive index, and where a ratio of the outer radius to the inner radius is less than 1.5.