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arXiv · 2305.15900

Polarization Independent Grating in GaN-on-Sapphire Photonic Integrated Circuit

Suraj·Shashwat Rathkanthiwar·Srinivasan Raghavan·Shankar Kumar Selvaraja
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Abstract

In this work, we report the realization of a polarization-insensitive grating coupler, single-mode waveguide, and ring resonator in the GaN-on-Sapphire platform. We provide a detailed demonstration of the material characterization, device simulation, and experimental results. We achieve a grating coupler efficiency of -5.2 dB/coupler with a 1dB and 3dB bandwidth of 40 nm and 80 nm, respectively. We measure a single-mode waveguide loss of -6 dB/cm. The losses measured here are the lowest in a GaN-on-Sapphire photonic circuit. This demonstration provides opportunities for the development of on-chip linear and non-linear optical processes using the GaN-on-Sapphire platform. To the best of our knowledge, this is the first demonstration of an integrated photonic device using a GaN HEMT stack with 2D electron gas.

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Suraj, Shashwat Rathkanthiwar, Srinivasan Raghavan, Shankar Kumar Selvaraja. 2023-05-25. Polarization Independent Grating in GaN-on-Sapphire Photonic Integrated Circuit. https://doi.org/10.1364/oe.487389

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