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arXiv · 2310.04293

Measurement of ultrashort bi-photon correlation times with an integrated two-colour broadband SU(1,1)-interferometer

F. Roeder·R. Pollmann·M. Stefszky·M. Santandrea·K. -H. Luo·V. Quiring·R. Ricken·C. Eigner·B. Brecht·C. Silberhorn
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Abstract

The bi-photon correlation time, a measure for the conditional uncertainty in the temporal arrival of two photons from a photon pair source, is a key performance identifier for many quantum spectroscopy applications, with shorter correlation times typically yielding better performance. Furthermore, it provides fundamental insight into the effects of dispersion on the bi-photon state. Here, we retrieve ultrashort bi-photon correlation times of around $100\,\mathrm{fs}$ by measuring simultaneously spectral and temporal interferograms at the output of an SU(1,1) interferometer based on an integrated broadband parametric down-conversion source in a $\mathrm{Ti:LiNbO}_3$ waveguide

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F. Roeder, R. Pollmann, M. Stefszky, M. Santandrea, K. -H. Luo, V. Quiring, R. Ricken, C. Eigner, B. Brecht, C. Silberhorn. 2023-10-06. Measurement of ultrashort bi-photon correlation times with an integrated two-colour broadband SU(1,1)-interferometer. https://doi.org/10.1103/prxquantum.5.020350

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