Holographic Storage of Biphoton Entanglement

Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
Physical Review Letters (Impact Factor: 7.73). 04/2012; 108(21). DOI: 10.1103/PhysRevLett.108.210501
Source: arXiv

ABSTRACT Coherent and reversible storage of multi-photon entanglement with a multimode
quantum memory is essential for scalable all-optical quantum information
processing. Although single photon has been successfully stored in different
quantum systems, storage of multi-photon entanglement remains challenging
because of the critical requirement for coherent control of photonic
entanglement source, multimode quantum memory, and quantum interface between
them. Here we demonstrate a coherent and reversible storage of biphoton
Bell-type entanglement with a holographic multimode atomic-ensemble-based
quantum memory. The retrieved biphoton entanglement violates Bell's inequality
for 1 microsecond storage time and a memory-process fidelity of 98% is
demonstrated by quantum state tomography.

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