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arXiv · 0906.3141

Demonstration of a universal one-way quantum quadratic phase gate

Yoshichika Miwa·Jun-ichi Yoshikawa·Peter van Loock·Akira Furusawa
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Abstract

We demonstrate a quadratic phase gate for one-way quantum computation in the continuous-variable regime. This canonical gate, together with phase-space displacements and Fourier rotations, completes the set of universal gates for realizing any single-mode Gaussian transformation such as arbitrary squeezing. As opposed to previous implementations of measurement-based squeezers, the current gate is fully controlled by the local oscillator phase of the homodyne detector. Verifying this controllability, we give an experimental demonstration of the principles of one-way quantum computation over continuous variables. Moreover, we can observe sub-shot-noise quadrature variances in the output states, confirming that nonclassical states are created through cluster computation.

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Yoshichika Miwa, Jun-ichi Yoshikawa, Peter van Loock, Akira Furusawa. 2009-06-17. Demonstration of a universal one-way quantum quadratic phase gate. https://doi.org/10.1103/physreva.80.050303

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