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arXiv · 2409.13110

Laser-written scalable sapphire integrated photonics platform

Mohan Wang·Patrick S. Salter·Frank P. Payne·Tongyu Liu·Martin J. Booth·Julian A. J. Fells
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Abstract

In this paper, we demonstrate the integration of photonic devices on sapphire substrates using multi-layer depressed cladding waveguides at both 780 nm and 1550 nm. The devices are up to 10-cm long and written at depths down to 400 um. The propagation losses for single-mode guiding are ~ 0.6 dB/cm at 780 nm and ~ 0.7 dB/cm at 1550 nm. A number of structures have been fabricated with simultaneous single-mode and polarization independent operation: evanescently coupled waveguide arrays, Y-branch splitters, Mach-Zehnder interferometers, and a 2x2 directional-coupler. All the devices were fabricated using adaptive optics-assisted femtosecond laser direct writing with a customized laser writing algorithm. This work enables the integration of single-mode sapphire photonics devices in a scalable manner, enabling many applications in communications, imaging, computing, and sensing.

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Mohan Wang, Patrick S. Salter, Frank P. Payne, Tongyu Liu, Martin J. Booth, Julian A. J. Fells. 2024-09-19. Laser-written scalable sapphire integrated photonics platform. https://arxiv.org/abs/2409.13110

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