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arXiv · 0707.2880

Manipulating biphotonic qutrits

B. P. Lanyon·T. J. Weinhold·N. K. Langford·J. L. O'Brien·K. J. Resch·A. Gilchrist·A. G. White
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Abstract

Quantum information carriers with higher dimension than the canonical qubit offer significant advantages. However, manipulating such systems is extremely difficult. We show how measurement induced non-linearities can be employed to dramatically extend the range of possible transforms on biphotonic qutrits; the three level quantum systems formed by the polarisation of two photons in the same spatio-temporal mode. We fully characterise the biphoton-photon entanglement that underpins our technique, thereby realising the first instance of qubit-qutrit entanglement. We discuss an extension of our technique to generate qutrit-qutrit entanglement and to manipulate any bosonic encoding of quantum information.

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B. P. Lanyon, T. J. Weinhold, N. K. Langford, J. L. O'Brien, K. J. Resch, A. Gilchrist, A. G. White. 2007-10-16. Manipulating biphotonic qutrits. https://doi.org/10.1103/physrevlett.100.060504

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