Silicon induced in situ hole formation in optical fibers

Random hole optical fibers (RHOFs) represent a new class of holey fiber, which utilizes randomly sized and spaced porosity in the cladding region to confine light to the core region of the fiber. The porosity in the cladding region acts to lower the average refractive index relative to that of the core region. This paper presents studies on silicon induced in situ hole formation in optical fibers. Silicon powder was added to the optical fiber preform and during drawing of the optical fiber, the silicon powder caused the formation of bubbles which were subsequently drawn into tubes in the fiber.