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arXiv · 1710.00584

A resource-saving realization of the polarization-independent orbital-angular-momentum-preserving tunable beam splitter

Ya-Ping Li·Fang-Xiang Wang·Wei Chen·Guo-Wei Zhang·Zhen-Qiang Yin·De-Yong He·Shuang Wang·Guang-Can Guo·Zheng-Fu Han
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Abstract

Tunable beam splitter (TBS) is a fundamental component which has been widely used in optical experiments. We realize a polarization-independent orbital-angular-momentum-preserving TBS based on the combination of modified polarization beam splitters and half-wave plates. Greater than 30 dB of the extinction ratio of tunableness, lower than $6\%$ of polarization dependence and more than 20 dB of the extinction ratio of OAM preservation show the relatively good performance of the TBS. In addition, the TBS can save about 3/4 of the optical elements compared with the existing scheme to implement the same function\cite{yang2016experimental}, which makes it have great advantages in scalable applications. Using this TBS, we experimentally built a Sagnac interferometer with the mean visibility of more than $99\%$, which demonstrates its potential applications in quantum information process, such as quantum cryptography.

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Ya-Ping Li, Fang-Xiang Wang, Wei Chen, Guo-Wei Zhang, Zhen-Qiang Yin, De-Yong He, Shuang Wang, Guang-Can Guo, Zheng-Fu Han. 2017-10-02. A resource-saving realization of the polarization-independent orbital-angular-momentum-preserving tunable beam splitter. https://arxiv.org/abs/1710.00584

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