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arXiv · 1610.03239

Quantum frequency conversion between infrared and ultraviolet

Helge Rütz·Kai-Hong Luo·Hubertus Suche Christine Silberhorn
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Abstract

We report on the implementation of quantum frequency conversion (QFC) between infrared (IR) and ultraviolet (UV) wavelengths by using single-stage upconversion in a periodically poled KTP waveguide. Due to the monolithic waveguide design, we manage to transfer a telecommunication band input photon to the wavelength of the ionic dipole transition of Yb${}^{+}$ at 369.5 nm. The external (internal) conversion efficiency is around 5\% (10\%). The high energy pump used in this converter introduces a spontaneous parametric downconversion (SPDC) process, which is a cause for noise in the UV mode. Using this SPDC process, we show that the converter preserves non-classical correlations in the upconversion process, rendering this miniaturized interface a source for quantum states of light in the UV.

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Helge Rütz, Kai-Hong Luo, Hubertus Suche Christine Silberhorn. 2016-10-11. Quantum frequency conversion between infrared and ultraviolet. https://doi.org/10.1103/physrevapplied.7.024021

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