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Title: Generation and characterization of ultrabroadband polarization–frequency hyperentangled photons

We generate ultrabroadband photon pairs entangled in both polarization and frequency bins through an all-waveguided Sagnac source covering the entire optical C- and L-bands (1530–1625 nm). We perform comprehensive characterization of high-fidelity states in multiple dense wavelength-division multiplexed channels, achieving full tomography of effective four-qubit systems. Additionally, leveraging the inherent high dimensionality of frequency encoding and our electro-optic measurement approach, we demonstrate the scalability of our system to higher dimensions, reconstructing states in a 36-dimensional Hilbert space consisting of two polarization qubits and two frequency-bin qutrits. Our findings hold potential significance for quantum networking, particularly dense coding and entanglement distillation in wavelength-multiplexed quantum networks.

 
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Award ID(s):
1747426
NSF-PAR ID:
10474011
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Letters
Volume:
48
Issue:
22
ISSN:
0146-9592; OPLEDP
Format(s):
Medium: X Size: Article No. 6031
Size(s):
Article No. 6031
Sponsoring Org:
National Science Foundation
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