No abstract

The first fibre preforms with a Pb-doped silica core, free of other dopants, have been produced using chemical vapour deposition. The preforms have been used to fabricate holey optical fibres. The spectroscopic properties of the fibres have been studied in detail in the range 400 -1700 nm: we have measured the optical loss, constructed a three-dimensional luminescence excitation -emission graph and determined the decay time for the major luminescence peaks.