Freiburg 2019 – wissenschaftliches Programm
FM 84.7: Poster
Donnerstag, 26. September 2019, 16:30–18:30, Tents
Polarization-Preserving Quantum Frequency Conversion of 40Ca+-Resonant Photons to the Telecom C-Band — •Tobias Bauer, Matthias Bock, Stephan Kucera, Benjamin Kambs, Jan Arenskötter, Jürgen Eschner, and Christoph Becher — Universität des Saarlandes, FR Physik, Campus E2.6, 66123 Saarbrücken
In quantum communication networks information is stored in internal states of quantum nodes, which can be realized e.g. in trapped ions like 40Ca+. By transferring the states onto photons, it is possible to exchange information between these nodes over long distances via optical fiber links. In order to minimize attenuation in fibers, which is particularly high for typical transition frequencies of trapped ions, quantum frequency down-conversion of the transmitted photons to low-loss telecom bands is utilized .
We present a scheme for polarization-preserving quantum frequency conversion of 40Ca+-resonant photons to the telecom C-band. It relies on the difference frequency generation process 854 nm −1904 nm =1550 nm  in a PPLN waveguide, which is arranged in a Sagnac configuration to achieve polarization preservation. We will present the characterization of the converter, in particular of its conversion efficiency and noise count rates.
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