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arXiv · 1601.06697

Displacement of propagating squeezed microwave states

Kirill G. Fedorov·L. Zhong·S. Pogorzalek·P. Eder·M. Fischer·J. Goetz·E. Xie·F. Wulschner·K. Inomata·T. Yamamoto·Y. Nakamura·R. Di Candia·U. Las Heras·M. Sanz·E. Solano·E. P. Menzel·F. Deppe·A. Marx·R. Gross
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Abstract

Displacement of propagating quantum states of light is a fundamental operation for quantum communication. It enables fundamental studies on macroscopic quantum coherence and plays an important role in quantum teleportation protocols with continuous variables. In our experiments we have successfully implemented this operation for propagating squeezed microwave states. We demonstrate that, even for strong displacement amplitudes, there is no degradation of the squeezing level in the reconstructed quantum states. Furthermore, we confirm that path entanglement generated by using displaced squeezed states stays constant over a wide range of the displacement power.

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Kirill G. Fedorov, L. Zhong, S. Pogorzalek, P. Eder, M. Fischer, J. Goetz, E. Xie, F. Wulschner, K. Inomata, T. Yamamoto, Y. Nakamura, R. Di Candia, U. Las Heras, M. Sanz, E. Solano, E. P. Menzel, F. Deppe, A. Marx, R. Gross. 2016-01-25. Displacement of propagating squeezed microwave states. https://doi.org/10.1103/physrevlett.117.020502

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