Integrated photonics is a leading platform for quantum technologies including nonclassical state generation 1, 2, 3, 4, demonstration of quantum computational complexity 5 and secure quantum communications 6. As photonic circuits grow in complexity, full quantum tomography becomes impractical, and therefore an efficient method for their characterization 7, 8 is essential. Here we propose and demonstrate a fast, reliable method for reconstructing the two-photon state produced by an arbitrary quadratically nonlinear optical circuit. By establishing a rigorous correspondence between the generated quantum state and classical sum-frequency generation measurements from laser light, we overcome the limitations of previous approaches for lossy multi-mode devices 9, 10. We applied this protocol to a multi-channel nonlinear waveguide network and measured a 99.28±0.31% fidelity between classical and quantum characterization. This technique enables fast and precise evaluation of nonlinear quantum photonic networks, a crucial step towards complex, large-scale, device production.
Direct characterization of a nonlinear photonic circuit's wave function with laser light / Lenzini, F.; Poddubny, A. N.; Titchener, J.; Fisher, P.; Boes, A.; Kasture, S.; Haylock, B.; Villa, M.; Mitchell, A.; Solntsev, A. S.; Sukhorukov, A. A.; Lobino, M.. - In: LIGHT, SCIENCE & APPLICATIONS. - ISSN 2095-5545. - 7:1(2018), pp. 17143-17143. [10.1038/lsa.2017.143]
Direct characterization of a nonlinear photonic circuit's wave function with laser light
Lobino M.
2018-01-01
Abstract
Integrated photonics is a leading platform for quantum technologies including nonclassical state generation 1, 2, 3, 4, demonstration of quantum computational complexity 5 and secure quantum communications 6. As photonic circuits grow in complexity, full quantum tomography becomes impractical, and therefore an efficient method for their characterization 7, 8 is essential. Here we propose and demonstrate a fast, reliable method for reconstructing the two-photon state produced by an arbitrary quadratically nonlinear optical circuit. By establishing a rigorous correspondence between the generated quantum state and classical sum-frequency generation measurements from laser light, we overcome the limitations of previous approaches for lossy multi-mode devices 9, 10. We applied this protocol to a multi-channel nonlinear waveguide network and measured a 99.28±0.31% fidelity between classical and quantum characterization. This technique enables fast and precise evaluation of nonlinear quantum photonic networks, a crucial step towards complex, large-scale, device production.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione
