Simple idea to demonstrate entangled photon pair
Hsin-Pin Lo (羅信斌)1*, Atsushi Yabushita (籔下篤史)1, Takayoshi Kobayashi (小林孝嘉)1,2
1Department of Electrophysics, National Chiao Tung University, Hsinchu, Taiwan
2Advanced Ultrafast Laser Research Center, The University of Electro-Communications, Tokyo, Japan
* presenting author:Hsin-Pin Lo,
Recently, we focused on the polarization-entangled photon pair generation in NCTU. There are cone [1, 2] and beamlike [3, 4] entangled pair were demonstrated through the spontaneous parametric down conversion (SPDC) process and also used in the research topics of quantum information science. In this presentation, I will briefly introduce how to generate the entangled photon pair in polarization. Here, we propose a really simple method to find out the direction of photon pair (λ=804 nm) by the pump laser and couple into the fiber. From the measurement of quantum correlation, we can find a high fidelity (F=0.906±0.04) entanglement [5]. This method can help to demonstrate the quantum communication in the future.

[1] Hsin-Pin Lo, Che-Ming Li, Atsushi Yabushita, Yueh-Nan Chen, Chih-Wei Luo, and Takayoshi Kobayashi, “Experimental violation of Bell inequalities for multi-dimensional systems”, arXiv: 1501.06429.
[2] Hsin-Pin Lo, Atsushi Yabushita, and Li-Yi Hsu, “Exploring steering effects using Bell tests”, PRA 89, 022115 (2014).
[3] Hsin-Pin Lo, Atsushi Yabushita*, Chih-Wei Luo, Pochung Chen, and Takayoshi Kobayashi, “Beamlike photon pairs entangled by a 2 x 2 fiber”, PRA 84, 022301 (2011).
[4] Hsin-Pin Lo, Atsushi Yabushita, Chih-Wei Luo, Pochung Chen, and Takayoshi Kobayashi, “Beamlike photon-pair generation for two-photon interference and polarization entanglement”, PRA 82, 022313 (2011).
[5] Hsin-Pin Lo, Atsushi Yabushita, and Takayoshi Kobayashi, “Photon doughnut-shaped pair for easy production of entangled photon pairs ”, PRA 91, 062327 (2015).

Keywords: Entanglement, Entangled photon pair, Quantum information experiment