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arXiv · 1502.06433

Resilience of hybrid optical angular momentum qubits to turbulence

Osvaldo Jiménez Farías·Vincenzo D'Ambrosio·Caterina Taballione·Fabrizio Bisesto·Sergei Slussarenko·Leandro Aolita·Lorenzo Marrucci·Stephen P. Walborn·Fabio Sciarrino
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Abstract

Recent schemes to encode quantum information into the total angular momentum of light, defining rotation-invariant hybrid qubits composed of the polarization and orbital angular momentum degrees of freedom, present interesting applications for quantum information technology. However, there remains the question as to how detrimental effects such as random spatial perturbations affect these encodings. Here, we demon- strate that alignment-free quantum communication through a turbulent channel based on hybrid qubits can be achieved with unit transmission fidelity. In our experiment, alignment-free qubits are produced with q-plates and sent through a homemade tur- bulence chamber. The decoding procedure, also realized with q-plates, relies on both degrees of freedom and renders an intrinsic error-filtering mechanism that maps errors into losses.

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Osvaldo Jiménez Farías, Vincenzo D'Ambrosio, Caterina Taballione, Fabrizio Bisesto, Sergei Slussarenko, Leandro Aolita, Lorenzo Marrucci, Stephen P. Walborn, Fabio Sciarrino. 2015-02-23. Resilience of hybrid optical angular momentum qubits to turbulence. https://doi.org/10.1038/srep08424

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