Active fibre devices are conventionally manufactured using MCVD technique. Recently it has been shown that nearly equivalent results can also be obtained with sol–gel technology. Now we present a novel technique allowing simplification of the manufacturing process even more. The required constituents are mixed in the form of dry micro- and nano-sized particles. A silica glass tube forming the future core region of a fibre preform is filled with a powder mix of SiO2, 1% Nd (as Nd2O3) and 10% Al (as Al2O3). This tube is mounted in the centre of a larger tube forming the future cladding. The empty space between the two tubes is filled with SiO2 powder. After preheating, the evacuated preform is drawn to a fibre. A length of 45cm, cladding-pumped with a diode laser at 808nm as well as a core-pumped fibre of 5.1cm length showed laser action between 1.05 and 1.1μm.
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