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arXiv · 1409.4908

Tuneable quantum interference in a 3D integrated circuit

Zachary Chaboyer·Thomas Meany·L. G. Helt·Michael J. Withford·M. J. Steel
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Abstract

Integrated photonics promises solutions to questions of stability, complexity, and size in quantum optics. Advances in tunable and non-planar integrated platforms, such laser-inscribed photonics, continue to bring the realisation of quantum advantages in computation and metrology ever closer, perhaps most easily seen in multi-path interferometry. Here we demonstrate control of two-photon interference in a chip-scale 3D multi-path interferometer, showing a reduced periodicity and enhanced visibility compared to single photon measurements. Observed non-classical visibilities are widely tunable, and explained well by theoretical predictions based on classical measurements. With these predictions we extract a Fisher information approaching a theoretical maximum, demonstrating the capability of the device for quantum enhanced phase measurements.

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Zachary Chaboyer, Thomas Meany, L. G. Helt, Michael J. Withford, M. J. Steel. 2014-09-17. Tuneable quantum interference in a 3D integrated circuit. https://doi.org/10.1038/srep09601

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