Highly nonlinear optical waveguide structure with enhanced nonlinearity and mechanical robustness

A method for fabricating a hybrid optical waveguide structure, the method comprising:

• inserting an optical waveguide into a hollow cylinder of a coating material, the coating material differing from a material of the optical waveguide, the optical waveguide comprising a core and a surrounding cladding for substantially confining a mode of light traveling therein;
• applying heat at a temperature which induces a uniform collapse of the coating material over the optical waveguide, to form a hybrid optical waveguide;
• and
• upon the heat being applied, forming a new optical waveguide by stretching the hybrid optical waveguide until a diameter of the hybrid optical waveguide is reduced to cause the surrounding cladding to form part of the core and the coating material to become a cladding of the new optical waveguide, thereby better confining the mode of light into the core and the surrounding cladding of the optical waveguide once stretched.