Nature Photonics Research Highlight: Stronger Nanofibres

Stronger Nanofibres

J. Lightwave Technol. 29, 1018–1025 (2011)

Nanostructured optical fibres offer custom-designed dispersion, high strength and high fabrication efficiency properties that make them attractive for use in a wide range of miniature highperformance photonic devices. Although a nanostructured fibre can be fabricated in the same way as a microstructured fibre — by drawing a structural preform at the glass-softening temperature — slight non-uniformities in the preform can cause the fibre to deform or even collapse.

Meisong Liao and co-workers in Japan have now circumvented some of the difficulties associated with nanostructured fibre fabrication by analysing the non-uniformity of hole evolution during the fibre-drawing process. The researchers found that hole size is a key factor in the stability of the fibre, and that small holes increase the likelihood of fibre collapse. The researchers claim to have fabricated a fibre with the smallest ever fibre core by using an inflation method to increase the hole size. For a 120-nm long nanostructured fibre, they achieved a glass bridge thickness of only a few tens of nanometres. They also showed that high drawing temperatures cause an increase in surface tension but a significant decrease in viscosity, which leads to fibre distortion.