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arXiv · 0903.2903

Measuring Qutrit-Qutrit Entanglement of Orbital Angular Momentum States of an Atomic Ensemble and a Photon

R. Inoue·T. Yonehara·Y. Miyamoto·M. Koashi·M. Kozuma
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Abstract

Three-dimensional entanglement of orbital angular momentum states of an atomic qutrit and a single photon qutrit has been observed. Their full state was reconstructed using quantum state tomography. The fidelity to the maximally entangled state of Schmidt rank 3 exceeds the threshold 2/3. This result confirms that the density matrix cannot be decomposed into ensemble of pure states of Schmidt rank 1 or 2. That is, the Schmidt number of the density matrix must be equal to or greater than 3.

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R. Inoue, T. Yonehara, Y. Miyamoto, M. Koashi, M. Kozuma. 2009-09-12. Measuring Qutrit-Qutrit Entanglement of Orbital Angular Momentum States of an Atomic Ensemble and a Photon. https://doi.org/10.1103/physrevlett.103.110503

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