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arXiv · 2305.11157

Programmable multi-photon quantum interference in a single spatial mode

Lorenzo Carosini·Virginia Oddi·Francesco Giorgino·Lena M. Hansen·Benoit Seron·Simone Piacentini·Tobias Guggemos·Iris Agresti·Juan Carlos Loredo·Philip Walther
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Abstract

The interference of non-classical states of light enables quantum-enhanced applications reaching from metrology to computation. Most commonly, the polarisation or spatial location of single photons are used as addressable degrees-of-freedom for turning these applications into praxis. However, the scale-up for the processing of a large number of photons of such architectures is very resource demanding due to the rapidily increasing number of components, such as optical elements, photon sources and detectors. Here we demonstrate a resource-efficient architecture for multi-photon processing based on time-bin encoding in a single spatial mode. We employ an efficient quantum dot single-photon source, and a fast programmable time-bin interferometer, to observe the interference of up to 8 photons in 16 modes, all recorded only with one detector--thus considerably reducing the physical overhead previously needed for achieving equivalent tasks. Our results can form the basis for a future universal photonics quantum processor operating in a single spatial mode.

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Lorenzo Carosini, Virginia Oddi, Francesco Giorgino, Lena M. Hansen, Benoit Seron, Simone Piacentini, Tobias Guggemos, Iris Agresti, Juan Carlos Loredo, Philip Walther. 2023-05-18. Programmable multi-photon quantum interference in a single spatial mode. https://doi.org/10.1126/sciadv.adj09

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