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arXiv · 2504.04157

Fabrication of semi-cylindrical channels for one-dimensional fiber array edge couplers

Sakthi Priya Amirtharaj·Saandeep Peesapati·Sirshi S Ram·Sivarama Krishnan·Anil Prabhakar
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Abstract

Photonic Integrated Circuits (PICs) are essential for high-speed and compact optoelectronic applications, yet efficient optical coupling to PIC remains a critical challenge, where minimizing insertion losses is crucial for high-performance applications. Fiber arrays are commonly used as edge couplers for PICs. In this work, we demonstrate the fabrication of semi-cylindrical channels on glass substrates using femtosecond laser micromachining for fiber arrays edge couplers. This method enables the formation of narrow, well-defined grooves in glass substrates with submicron accuracy, facilitating reliable fiber positioning for improved coupling efficiency. Experimental results demonstrate the feasibility of this approach for dense fiber arrays, with a narrow separation of \sim 3 {\mu}m.

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Sakthi Priya Amirtharaj, Saandeep Peesapati, Sirshi S Ram, Sivarama Krishnan, Anil Prabhakar. 2025-04-05. Fabrication of semi-cylindrical channels for one-dimensional fiber array edge couplers. https://arxiv.org/abs/2504.04157

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