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arXiv · 1405.2694

Strain-optic active control for quantum integrated photonics

Peter C. Humphreys·Benjamin J. Metcalf·Justin B. Spring·Merritt Moore·Patrick S. Salter·Martin J. Booth·W. Steven Kolthammer·Ian A. Walmsley
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Abstract

We present a practical method for active phase control on a photonic chip that has immediate applications in quantum photonics. Our approach uses strain-optic modification of the refractive index of individual waveguides, effected by a millimeter-scale mechanical actuator. The resulting phase change of propagating optical fields is rapid and polarization-dependent, enabling quantum applications that require active control and polarization encoding. We demonstrate strain-optic control of non-classical states of light in silica, showing the generation of 2-photon polarisation N00N states by manipulating Hong-Ou-Mandel interference. We also demonstrate switching times of a few microseconds, which are sufficient for silica-based feed-forward control of photonic quantum states.

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Peter C. Humphreys, Benjamin J. Metcalf, Justin B. Spring, Merritt Moore, Patrick S. Salter, Martin J. Booth, W. Steven Kolthammer, Ian A. Walmsley. 2014-05-12. Strain-optic active control for quantum integrated photonics. https://doi.org/10.1364/oe.22.021719

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