UV defined nanoporous liquid core waveguides

Nanoporous liquid core waveguides, where both core and cladding are made from the same material, are presented. The nanoporous polymer used is intrinsically hydrophobic, but selective UV exposure enables it to infiltrate with an aqueous solution, thus raising the refractive index from 1.26 to 1.42. The waveguides are promising for integrated optofluidic sensor systems, where a long optical interaction length can be achieved with a small fluid sample. The propagation loss of a 200×200 μm waveguide is measured to 0.62 dB/mm.