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arXiv · 2009.14190

Group-velocity dispersion engineering of tantala integrated photonics

Jennifer A. Black·Richelle Streater·Kieran F. Lamee·David R. Carlson·Su-Peng Yu·Scott B. Papp
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Abstract

Designing integrated photonics, especially to leverage Kerr-nonlinear optics, requires accurate and precise knowledge of refractive index across the visible to infrared spectral ranges. Tantala (Ta_2O_5) is an emerging material platform for integrated photonics and nanophotonics that offers broadband ultralow loss, moderately high nonlinearity, and advantages for scalable and heterogeneous integration. We present refractive-index measurements on a thin film of tantala, and we explore the efficacy of this data for group-velocity dispersion (GVD) engineering with waveguide and ring-resonator devices. In particular, the observed spectral extent of supercontinuum generation in fabricated waveguides, and the wavelength dependence of free spectral range (FSR) in optical resonators provide a sensitive test of our integrated-photonics design process. Our work opens up new design possibilities with tantala, including with octave-spanning soliton microcombs.

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Jennifer A. Black, Richelle Streater, Kieran F. Lamee, David R. Carlson, Su-Peng Yu, Scott B. Papp. 2020-09-29. Group-velocity dispersion engineering of tantala integrated photonics. https://doi.org/10.1364/ol.414095

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