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Acta Physica Sinica

Design of high brightness entangled source based on periodically poled KTiOPO4 crystal

Ji-Gang Ren, Zhang Han, Cai Xin-Dong, Juan Yin, Zhou Fei, Peng Cheng-Zhi, (1)清华大学物理系，北京 100084; (2)清华大学物理系，北京 100084；中国科学技术大学近代物理系，合肥微尺度物质科学国家实验室，合肥 230026; (3)中国科学技术大学近代物理系，合肥微尺度物质科学国家实验室，合肥 230026

Published Jan 1, 2009• 3 citations

Abstract

Entangled states are key resource for quantum information processing. In linear optics quantum computing，the most widely used entanglement resource is polarization entangled photon pairs generated via type-Ⅱ spontaneous parametric down-conversion. However，the brightness is not sufficient to perform quantum communication experiment between ground and satellite. In this paper we have developed a high-brightness entangled resource based on periodic polarization and quasi-phase marched periodically poled KTiOPO4 crystal. The number of generated entangled pairs is about 1.6×104s-1mW-1 and the visibility is 27∶1. Our source is with about one order of magnitude brighter than previous sources based on β-barium borate crystal. This leads to an immediate possibility for applications in the field of quantum key distribution，quantum teleportation and quantum computation. Particularly it would form a solid basis for future global quantum network.

DOI: 10.7498/aps.58.5169

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