Demonstration of analyzers for multimode photonic time-bin qubits

作     者：Jeongwan Jin Sascha Agne Jean-Philippe Bourgoin Yanbao Zhang Norbert Lütkenhaus Thomas Jennewein 

作者机构：Institute for Quantum Computing University of Waterloo 200 University Avenue West Waterloo Ontario N2L 3G1 Canada Department of Physics and Astronomy University of Waterloo 200 University Avenue West Waterloo Ontario N2L 3G1 Canada Quantum Information Science Program Canadian Institute for Advanced Research Toronto Ontario M5G 1Z8 Canada 

出 版 物：《Physical Review A》 (Phys. Rev. A)

年 卷 期：2018年第97卷第4期

页      面：043847-043847页

核心收录：

基　　金：Office of Naval Research, ONR Ontario Research Foundation, ORF Canada Foundation for Innovation, CFI Industry Canada Canadian Institute for Advanced Research, CIFAR 

主　　题：Quantum communication 

摘      要：We demonstrate two approaches for unbalanced interferometers as time-bin qubit analyzers for quantum communication, robust against mode distortions and polarization effects as expected from free-space quantum communication systems including wavefront deformations, path fluctuations, pointing errors, and optical elements. Despite strong spatial and temporal distortions of the optical mode of a time-bin qubit, entangled with a separate polarization qubit, we verify entanglement using the Negative Partial Transpose, with the measured visibility of up to 0.85±0.01. The robustness of the analyzers is further demonstrated for various angles of incidence up to 0.2∘. The output of the interferometers is coupled into multimode fiber yielding a high system throughput of 0.74. Therefore, these analyzers are suitable and efficient for quantum communication over multimode optical channels.