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arXiv · 2009.09421

Quantum Information Transfer between a Two-Level and a Four-Level Quantum System

Tianfeng Feng·Qiao Xu·Linxiang Zhou·Maolin Luo·Wuhong Zhang·Xiaoqi Zhou
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Abstract

Quantum mechanics provides a disembodied way to transfer quantum information from one quantum object to another. In theory, this quantum information transfer can occur between quantum objects of any dimension, yet the reported experiments of quantum information transfer to date have mainly focused on the cases where the quantum objects have the same dimension. Here we theoretically propose and experimentally demonstrate a scheme for quantum information transfer between quantum objects of different dimensions.By using an optical qubit-ququart entangling gate, we observe the transfer of quantum information between two photons with different dimensions, including the flow of quantum information from a four-dimensional photon to a two-dimensional photon and vice versa.The fidelities of the quantum information transfer range from 0.700 to 0.917, all above the classical limit of 2/3. Our work sheds light on a new direction for quantum information transfer and demonstrates our ability to implement entangling operations beyond two-level quantum systems.

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Tianfeng Feng, Qiao Xu, Linxiang Zhou, Maolin Luo, Wuhong Zhang, Xiaoqi Zhou. 2022-02-21. Quantum Information Transfer between a Two-Level and a Four-Level Quantum System. https://doi.org/10.1364/prj.461283

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