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arXiv · 1606.07492

Deterministic Generation of a Cluster State of Entangled Photons

Ido Schwartz·Dan Cogan·Emma R. Schmidgall·Yaroslav Don·Liron Gantz·Oded Kenneth·Netanel H. Lindner·David Gershoni
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Abstract

We use semiconductor quantum dots, "artificial atoms," to implement a scheme for deterministic generation of long strings of entangled photons in a cluster state, an important resource for quantum information processing. We demonstrate a prototype device which produces strings of a few hundred photons in which the entanglement persists over 5 sequential photons. The implementation follows a proposal by Lindner and Rudolph (Phys. Rev. Lett. 2009) which suggested periodic timed excitation of a precessing electron spin as a mechanism for entangling the electron spin with the polarization of the sequentially emitted photons. In our realization, the entangling qubit is a quantum dot confined dark exciton. By performing full quantum process tomography, we obtain the process map which fully characterizes the evolution of the system, containing the dark exciton and n photons after n applications of the periodic excitations. Our implementation may greatly reduce the resources needed for quantum information processing.

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Ido Schwartz, Dan Cogan, Emma R. Schmidgall, Yaroslav Don, Liron Gantz, Oded Kenneth, Netanel H. Lindner, David Gershoni. 2016-06-23. Deterministic Generation of a Cluster State of Entangled Photons. https://doi.org/10.1126/science.aah4758

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