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arXiv · 1909.13530

Lithium niobate waveguides with high-index contrast and preserved nonlinearity fabricated by High Vacuum Vapor-phase Proton Exchange

Alicia Petronela Rambu·Alin Marian Apetrei·Florent Doutre·Herve Tronche·Vasile Tiron·Marc De Micheli·Sorin Tascu
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Abstract

Highly confining waveguides without degraded nonlinear coefficient and low propagation losses have been fabricated in lithium niobate by a new process that we called High Vacuum Vapor-phase Proton Exchange (HiVac-VPE). Index contrast, index profile, nonlinearity and crystallographic phases are carefully investigated. Original analysis of index profiles indicates that the waveguides contains sub-layers whose depths are depending on the exchange durations. Propagation behavior, propagation losses and Second Harmonic Generation (SHG) response of HiVac-VPE channel waveguides are investigated at telecom wavelength. The results recommend HiVac-VPE as very promising technique for fabricating efficient nonlinear photonic integrated circuits in LN crystals.

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Alicia Petronela Rambu, Alin Marian Apetrei, Florent Doutre, Herve Tronche, Vasile Tiron, Marc De Micheli, Sorin Tascu. 2019-09-30. Lithium niobate waveguides with high-index contrast and preserved nonlinearity fabricated by High Vacuum Vapor-phase Proton Exchange. https://doi.org/10.1364/prj.8.000008

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