Short low-loss nanowire tapers on singlemode fibres

Abstract

The successful production of very short, very low-loss nanowire tapers from singlemode optical fibres is reported. A pre-heated taper process in which the fibre is pre-necked is introduced. A waist diameter of 400 nm is found to be the point of delineation between strong guidance (>400 nm) and weak guidance (<400 nm) in these structures.