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arXiv · 1805.11286

Informationally symmetrical Bell state preparation and measurement

Yong-Su Kim·Tanumoy Pramanik·Young-Wook Cho·Ming Yang·Sang-Wook Han·Sang-Yun Lee·Sung Moon
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Abstract

Bell state measurement (BSM) plays crucial roles in photonic quantum information processing. The standard linear optical BSM is based on Hong-Ou-Mandel interference where two photons meet and interfere at a beamsplitter (BS). However, a generalized two-photon interference is not based on photon-photon interaction, but interference between two-photon probability amplitudes. Therefore, it might be possible to implement BSM without interfering photons at a BS. Here, we investigate a linear optical BSM scheme which does not require two photon overlapping at a BS. By unleashing the two photon coexistence condition, it can be symmetrically divided into two parties. The symmetrically dividable property suggests informationally symmetrical BSM between remote parties without a third party. We also present that our BSM scheme can be used for Bell state preparation between remote parties without a third party. Since our BSM scheme can be easily extended to multiple photons, it can be useful for various quantum communication applications.

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Yong-Su Kim, Tanumoy Pramanik, Young-Wook Cho, Ming Yang, Sang-Wook Han, Sang-Yun Lee, Sung Moon. 2018-05-29. Informationally symmetrical Bell state preparation and measurement. https://doi.org/10.1364/oe.26.029539

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