Evanescent wave gas sensing using microstructure fibre

Microstructure fibres (MFs) or holey fibre (HFs), which incorporate air-holes within the silica cladding region, have attracted significant attention recently. We report the first experimental demonstration of evanescent wave gas detection with a silica-air microstructure fibre. Detection sensitivity of /spl sim/5.5% that of direction absorption spectroscopy per equal length has been achieved.