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arXiv · 2403.01115

Tunable double notch filter on thin-film lithium niobate platform

Songyan Hou·Hao Hu·Zhihong Liu·Weichuan Xing·Jincheng Zhang·Yue Hao
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Abstract

Tunable optical filter at the chip scale plays a crucial role in fulfilling the need for the reconfigurability in channel routing, optical switching, and wavelength division multiplexing systems. In this letter, we propose a tunable double notch filter on thin-film lithium niobate using dual micro-ring architecture. This unique integrated filter is essential for complex photonic integrated circuits, along with multiple channels and various frequency spacing. With only one loaded voltage, the device demonstrates a wide frequency spacing tunability from 16.1 GHz to 89.9 GHz by reversely tunning the resonances of the two micro-rings while the center wavelength between the two resonances remains unaltered. Moreover, by utilizing the pronounced electro-optic properties of lithium niobate, associated with the tight light confinement nanophotonic waveguides, the device demonstrates a spacing tunability of 0.82 GHz/V and a contrast of 10~16 dB. In addition, the device has an ultracompact footprint of 0.0248 mm2.

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Songyan Hou, Hao Hu, Zhihong Liu, Weichuan Xing, Jincheng Zhang, Yue Hao. 2024-03-02. Tunable double notch filter on thin-film lithium niobate platform. https://doi.org/10.1364/ol.505362

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