Gamma irradiated thermoluminescence response of Ge-doped SiO2 fibre

•Fabricated tailor-made 6 mol% Ge-doped SiO2 Fibre of different diameters.•The smallest diameter fibre shows the greatest TL response.•TL yield of all fibres show linear response with gamma dose.•All fibres show maximum peak in glow curve between 250–310 °C.•High response tailor-made fibre suitable for use as a TL dosimeter.

Over the past decade and more, considerable interest has been shown in the thermoluminescence (TL) properties of silica-based single-mode optical fibres, in particular investigating potential ionising radiation dosimetry applications. Herein, study has been made of TL glow curve, dose response, reproducibility and fading of 6 mol% Ge-doped silica, fabricated in-house and produced in the form of cylindrical fibres. Three different pairings of doped-core and silica cladding diameters were produced: (40, 241) µm, (80, 483) µm and (100, 604) µm. The TL results were compared against that of TLD-100, one of the most sensitive commercially available LiF-based TL media. For all three pairings of diameters, closely similar TL glow curve were obtained, formed of a single peaked structure with a maximum TL yield located between the temperatures 250 and 310 °C. The TL yield of the fibres were linear over the range of doses investigated, from 1 Gy up to 10 Gy, their dose response exceeding that of TLD-100, the samples also being found to be reusable, without evidence of degradation.