Number Resolving, Mode-Selective Detection of High-Dimensional Correlated Photons

Misagh Izadi, Yuping Huang, Santosh Kumar, SIQUN DENG, Daniel Alejandro Lopez Martinez, Chitra Madhavi vadlamani, Yifan Du, Utkal Pandurangi

Published Oct 28, 2026• 0 citations

Publisher

Abstract

High-dimensional encoding in time-frequency and photon-number degrees of freedom promises photon-efficient quantum communication, but requires detectors that are both temporal-mode selective and photon-number resolving. Here we demonstrate time-correlated single-photon detection combining both capabilities. A train of shaped pump pulses drives quantum frequency up-conversion to select a chosen temporal mode, and the converted photons are counted with a photon-number-resolving detector. Applying to a photon-pair source by spontaneous parametric downconversion into signal and idler bands, we demonstrate direct sampling of the high-dimensional correlated quantum states on compound time-frequency and photon number bases. Our measurements show that the up-converted photons in each band exhibit thermal photon-number statistics, indicating strong single-mode selection. We reconstruct joint temporal intensities conditioned on one and two photon pairs, revealing signal-idler correlations in both time-frequency and photon number. Together, these results establish a unified technology framework linking high-dimensional quantum correlations, mode-selective photon measurement, and photon-number resolved detection. This approach provides a route to characterizing multimode photon-pair sources and to larger time-frequency and photon-number alphabets for high-dimensional quantum communication and information processing.

DOI: 10.1364/opticaopen.34790205

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