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Demonstration of deterministic and high fidelity squeezing of quantum information

Jun-ichi Yoshikawa·Toshiki Hayashi·Takayuki Akiyama·Nobuyuki Takei·Alexander Huck·Ulrik L. Andersen·Akira Furusawa
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Abstract

By employing at recent proposal (R. Filip, P. Marek and U.L. Andersen, Phys. Rev. A {\bf 71}, 042308 (2005) \cite{Filip05.pra}), we experimentally demonstrate a universal, deterministic and high-fidelity squeezing transformation of an optical field. It relies only on linear optics, homodyne detection, feedforward and an ancillary squeezed vacuum state, thus direct interaction between a strong pump and the quantum state is circumvented. We demonstrate three different squeezing levels for a coherent state input. This scheme is highly suitable for the fault-tolerant squeezing transformation in a continuous variable quantum computer.

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Jun-ichi Yoshikawa, Toshiki Hayashi, Takayuki Akiyama, Nobuyuki Takei, Alexander Huck, Ulrik L. Andersen, Akira Furusawa. 2007-11-09. Demonstration of deterministic and high fidelity squeezing of quantum information. https://doi.org/10.1103/physreva.76.060301

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