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Conference on Lasers and Electro-Optics

Demonstration of Unconditional Quantum Erasing for Continuous Variables

Yoshichika Miwa, Ryuji Ukai, Jun–ichi Yoshikawa, Radim Filip, Peter van Loock, Akira Furusawa

Published Jan 1, 2010• 0 citations
Publisher

Abstract

We demonstrate “undoing” quantum non-demolition gates by quantum erasing. In one-way quantum computation, these operations remove unwanted nodes from cluster states. Experimentally one mode was removed from two-mode and four-mode cluster state, respectively.
DOI
10.1364/qels.2010.jthe26

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We demonstrate experimentally how to remove an arbitrary node from a continuous-variable cluster state and how to shorten any quantum wires of such a state. These two basic operations, performed in an unconditional fashion, are a manifestation of quantum erasure and can be employed to obtain various graph states from an initial cluster state. Starting with a sufficiently large cluster, the resulting graph states can then be used for universal quantum information processing. In the experiment, all variations of this cluster shaping are demonstrated on a four-mode linear cluster state through homodyne measurements and feedforward.
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