Dr. Gilberto Brambilla, Southampton University

Silica optical fibres constitute the backbone of the internet and can be found in a multitude of applications including sensing (endoscopes), aerospace (gyroscopes) and manufacturing (high power lasers for cutting and welding). Despite being considered a mature consolidated technology, silica optical fibres are still investigated in a number of fields for a variety of applications ranging from high power fibre lasers to intrusion sensors. In this talk I will focus on specialty optical fibres with cores comparable to or smaller than the wavelength of light propagating in them. Optical micro- and nano-fibres exhibit extraordinary physical properties, such as mechanical strength or flexibility and they allow for the confinement of light to the diffraction limit over lengths limited only by loss. In addition, they also exhibit a significant evanescent field, with fractions of light as high as 99% propagating outside the waveguide physical boundary. This allows for an easy coupling with external structures and the realization of sub-millimeter resonators. Examples of applications include single exciton lasers, modulators and sensors.