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arXiv · 2101.03120

Fast imaging of multimode transverse-spectral correlations for twin photons

Michał Lipka·Michał Parniak
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Abstract

Hyperentangled photonic states - exhibiting nonclassical correlations in several degrees of freedom - offer improved performance of quantum optical communication and computation schemes. Experimentally, a hyperentanglement of transverse-wavevector and spectral modes can be obtained in a straightforward way with multimode parametric single-photon sources. Nevertheless, experimental characterization of such states remains challenging. Not only single-photon detection with high spatial resolution - a single-photon camera - is required, but also a suitable mode-converter to observe the spectral/temporal degree of freedom. We experimentally demonstrate a measurement of a full 4-dimensional transverse-wavevector-spectral correlations between pairs of photons produced in the non-collinear spontaneous parametric downconversion (SPDC). Utilization of a custom ultra-fast single-photon camera provides high resolution and a short measurement time.

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Michał Lipka, Michał Parniak. 2021-01-08. Fast imaging of multimode transverse-spectral correlations for twin photons. https://doi.org/10.1364/ol.417658

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