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arXiv · 2408.15139

Fast thermo-optic switching on silicon nitride platform through parity-time symmetry breaking

Ravi Pradip·Venkata Sai Akhil Varri·Liam McRae·Frank Brückerhoff-Plückelmann·Daniel Wendland·Anna P. Ovvyan·Shabnam Taheriniya·Wolfram Pernice·Simone Ferrari
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Abstract

This work demonstrates a fast thermo-optic switching mechanism on silicon nitride on insulator platform leveraging parity-time symmetry breaking. The cladding-free design enables low-loss optical propagation in a partially metal-covered waveguide, with the same metal layer serving as an integrated heater for rapid phase tuning. The fabricated device exhibits an 8.5 {\mu}s rise time for a {\pi} phase shift, despite the weak thermo-optic coefficient in silicon nitride. Additionally, the impact of thermal cross-talk is investigated and an insertion loss as low as 0.39 dB for a 100-{\mu}m-long heater-waveguide section is demonstrated.

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Ravi Pradip, Venkata Sai Akhil Varri, Liam McRae, Frank Brückerhoff-Plückelmann, Daniel Wendland, Anna P. Ovvyan, Shabnam Taheriniya, Wolfram Pernice, Simone Ferrari. 2024-08-27. Fast thermo-optic switching on silicon nitride platform through parity-time symmetry breaking. https://arxiv.org/abs/2408.15139

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