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arXiv · 2112.12671

Single-mode sapphire fiber Bragg grating

Mohan Wang·Patrick S. Salter·Frank P. Payne·Adrian Shipley·Stephen M. Morris·Martin J. Booth·Julian A. J. Fells
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Abstract

We present here the inscription of single-mode waveguides with Bragg gratings in sapphire. The waveguide Bragg gratings have a novel multi-layer depressed cladding design in the 1550 nm telecommunications waveband. The Bragg gratings have a narrow bandwidth (<0.5 nm) and have survived annealing at 1000{\deg}C. The structures are inscribed with femtosecond laser direct writing, using adaptive beam shaping with a non-immersion objective. A single-mode sapphire fiber Bragg grating is created by writing a waveguide with a Bragg grating within a 425 {\mu}m diameter sapphire optical fiber, providing significant potential for accurate remote sensing in ultra-extreme environments.

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Mohan Wang, Patrick S. Salter, Frank P. Payne, Adrian Shipley, Stephen M. Morris, Martin J. Booth, Julian A. J. Fells. 2021-12-23. Single-mode sapphire fiber Bragg grating. https://doi.org/10.1364/oe.446664

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