AIP Advances 4, 067124 (2014)

Tapered glass nanofibres with ultrahigh transmission have been fabricated by a US–French collaboration. Jonathan Hoffman and co-workers, from the Joint Quantum Institute (a partnership between the University of Maryland and the US National Institute of Standards and Technology) and the Université de Paris-Sud, report that their ultrathin optical glass fibres can transmit 99.95% of light. Such nanofibres are potentially useful for a diverse set of applications including optical trapping and sensing or coupling light to miniature photonic devices such as resonators or photonic crystals. The nanofibres are made by heating and pulling conventional silica optical fibres under optimal conditions of cleanliness, temperature and motor speed. The result is a tapered fibre that shrinks to a diameter as small as 530 nm when it is stretched by 84 mm. When propagating within the nanofibre, the fundamental optical mode experiences a loss of just 2.6 × 10−6 dB per millimetre. Such nanofibres can also support surprisingly high optical powers without suffering damage and more than 400 mW of 760 nm light from a Ti:sapphire laser has been successfully transmitted under high vacuum conditions.