Structure and propagation of modes of large mode area holey fibres

The authors report on the first demonstration of optical fibres based on the Ga:La:S system. Core-clad structures have been fabricated by the rod and tube method and pulled into lengths > 200m. Transmission over the wavelength range 1.0 to 6.5 µm, with fibre loss approaching the absorption and scattering level of the bulk glass, is obtained, opening the possibility of new fibre device applications of this promising glass host