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Title: Low-loss GaO x -core/SiO 2 -cladding planar waveguides on Si substrate

The unique properties of gallium oxide (GaOx) have drawn increasing interest as a material suitable for high-power electronic and optical applications. Herein, we report the demonstration of low-loss GaOx-core/SiO2-cladding waveguides on Si substrate. We present the fabrication process and annealing treatments of the waveguide devices, and we characterize the corresponding effects on optical transmission for 3 common wavelengths: 633 nm, 1064 nm, and 1550 nm. The best propagation loss achieved for these wavelengths is measured to be−<#comment/>0.4±<#comment/>0.1dB/cm,−<#comment/>0.3±<#comment/>0.2dB/cm, and−<#comment/>2.4±<#comment/>0.5dB/cm, respectively. We discuss the major waveguide loss mechanisms, followed by results of pump and probe experiments using visible/IR wavelengths for waveguides treated under various post-fabrication annealing conditions. We also show nonlinear measurements for a 250 fs laser beam to offer additional insights into the loss mechanisms, which are consistent with the linear optical transmission performances. High waveguide laser-induced damage threshold (LIDT) of>2.5J/cm2is measured at this pulse width, making GaOxa potential candidate for high-power integrated photonic devices.

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Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Express
1094-4087; OPEXFF
Page Range / eLocation ID:
Article No. 12475
Medium: X
Sponsoring Org:
National Science Foundation
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