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arXiv · 2306.04767

Fully guided and phase locked Ti:PPLN waveguide squeezing for applications in quantum sensing

Renato Domeneguetti·Michael Stefszky·Harald Herrmann·Christine Silberhorn·Ulrik L. Andersen·Jonas S. Neergaard-Nielsen·Tobias Gehring
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Abstract

This work reports a fully guided setup for single-mode squeezing generation on integrated titanium-indiffused periodically poled nonlinear resonators. A continuous wave laser beam is delivered and the squeezed field is collected by single-mode fibers, where up to -3.17(9) dB of useful squeezing is available in fibers. To showcase the usefulness of such a fiber-coupled device, we applied the generated squeezed light in a fiber-based phase sensing experiment, showing a quantum enhancement in the signal-to-noise ratio of 0.35 dB. Moreover, our investigation of photorefraction's impact on the cavity resonance condition suggests that it causes system instabilities at high powers.

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Renato Domeneguetti, Michael Stefszky, Harald Herrmann, Christine Silberhorn, Ulrik L. Andersen, Jonas S. Neergaard-Nielsen, Tobias Gehring. 2023-06-07. Fully guided and phase locked Ti:PPLN waveguide squeezing for applications in quantum sensing. https://doi.org/10.1364/ol.486654

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