Glass-on-Glass Fabrication of Bottle-Shaped Tunable Microlasers and their Applications

• Published in: Scientific reports 2016-04, Vol.6 (1), p.25152-25152, Article 25152
• Main Authors: Ward, Jonathan M., Yang, Yong, Nic Chormaic, Síle
• Format: Article
• Language: English
• Subjects: 639/624/1075/1083; 639/624/1107; 639/624/1111/1116; 639/624/399/1097; Carbon dioxide; Fabrication; Flow rates; Humanities and Social Sciences; Lasers; Melting; Melting point; multidisciplinary; Science; Silica; Wavelengths
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep25152

We describe a novel method for making microbottle-shaped lasers by using a CO 2 laser to melt Er:Yb glass onto silica microcapillaries or fibres. This is realised by the fact that the two glasses have different melting points. The CO 2 laser power is controlled to flow the doped glass around the silica cylinder. In the case of a capillary, the resulting geometry is a hollow, microbottle-shaped resonator. This is a simple method for fabricating a number of glass whispering gallery mode (WGM) lasers with a wide range of sizes on a single, micron-scale structure. The Er:Yb doped glass outer layer is pumped at 980 nm via a tapered optical fibre and WGM lasing is recorded around 1535 nm. This structure facilitates a new way to thermo-optically tune the microlaser modes by passing gas through the capillary. The cooling effect of the gas flow shifts the WGMs towards shorter wavelengths and thermal tuning of the lasing modes over 70 GHz is achieved. Results are fitted using the theory of hot wire anemometry, allowing the flow rate to be calibrated with a flow sensitivity as high as 72 GHz/sccm. Strain tuning of the microlaser modes by up to 60 GHz is also demonstrated.