| 1. |
- Vedovato, Francesco, et al.
(författare)
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Postselection-Loophole-Free Bell Violation with Genuine Time-Bin Entanglement
- 2018
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Ingår i: Physical Review Letters. - : AMER PHYSICAL SOC. - 0031-9007 .- 1079-7114. ; 121:19
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Tidskriftsartikel (refereegranskat)abstract
- Entanglement is an invaluable resource for fundamental tests of physics and the implementation of quantum information protocols such as device-independent secure communications. In particular, time-bin entanglement is widely exploited to reach these purposes both in free space and optical fiber propagation, due to the robustness and simplicity of its implementation. However, all existing realizations of time-bin entanglement suffer from an intrinsic postselection loophole, which undermines their usefulness. Here, we report the first experimental violation of Bells inequality with "genuine" time-bin entanglement, free of the postselection loophole. We introduced a novel function of the interferometers at the two measurement stations, that operate as fast synchronized optical switches. This scheme allowed us to obtain a postselection-loophole-free Bell violation of more than 9 standard deviations. Since our scheme is fully implementable using standard fiber-based components and is compatible with modem integrated photonics, our results pave the way for the distribution of genuine time-bin entanglement over long distances.
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| 2. |
- Tibaldi, Alberto, et al.
(författare)
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Analysis of Carrier Transport in Tunnel-Junction Vertical-Cavity Surface-Emitting Lasers by a Coupled Nonequilibrium Green's Function-Drift-Diffusion Approach
- 2020
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Ingår i: Physical Review Applied. - 2331-7019. ; 14:2
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Tidskriftsartikel (refereegranskat)abstract
- This work investigates carrier transport in tunnel junctions for vertical-cavity surface-emitting lasers (VCSELs). The study is performed with a quantum-corrected semiclassical approach, where tunneling is described rigorously with a nonequilibrium Green's function formalism based on a multiband description of the electronic structure. Validated with experimental results, the proposed approach provides a quantum -kinetic perspective of the tunneling process and paves the way toward a comprehensive theory of VCSELs, bridging the gap between semiclassical and quantum simulations.
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| 3. |
- Tibaldi, Alberto, et al.
(författare)
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Modeling Tunnel Junctions for VCSELs: A Self-Consistent NEGF-DD Approach
- 2020
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Ingår i: Proceedings of the International Conference on Numerical Simulation of Optoelectronic Devices, NUSOD. - 2158-3234. ; 2020-September, s. 67-68
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Konferensbidrag (refereegranskat)abstract
- In this work we investigate carrier transport in tunnel junctions for vertical-cavity surface-emitting lasers by a novel self-consistent simulation framework for semiconductor quantum devices. Based on a Poisson-drift-diffusion foundation, in this approach quantum features are described through a nonequilibrium Green's function formalism. The simulator is validated through a comparison with experimental results.
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| 4. |
- Tomasin, Marco, et al.
(författare)
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High-visibility time-bin entanglement for testing chained Bell inequalities
- 2017
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Ingår i: Physical Review A. - : AMER PHYSICAL SOC. - 2469-9926. ; 95:3
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Tidskriftsartikel (refereegranskat)abstract
- The violation of Bells inequality requires a well-designed experiment to validate the result. In experiments using energy-time and time-bin entanglement, initially proposed by Franson in 1989, there is an intrinsic loophole due to the high postselection. To obtain a violation in this type of experiment, a chained Bell inequality must be used. However, the local realism bound requires a high visibility in excess of 94.63% in the time-bin entangled state. In this work, we show how such a high visibility can be reached in order to violate a chained Bell inequality with six, eight, and ten terms.
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