Optical fiber with micro-structured cladding

1 21An optical fiber having a length can include a core and at least one cladding disposed about the core, where the one cladding can comprise at least first volumetric regions having a first refractive index nand second volumetric regions having a second refractive index n, different from n, and the first and second volumetric regions in any cross-section taken through the fiber can be randomly intermingled with one another, where the random intermingling of the first and second volumetric regions changes with changes in the location of the cross-section along the length of the fiber.