Abstract
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.
| Original language | English |
|---|---|
| Pages (from-to) | 6031-6034 |
| Number of pages | 4 |
| Journal | Optics Letters |
| Volume | 48 |
| Issue number | 22 |
| DOIs | |
| State | Published - 2023 |
Funding
Acknowledgment. This work was performed in part at Oak Ridge National Laboratory, operated by UT-Battelle for the US Department of Energy under contract no. DE-AC05-00OR22725. The authors would like to thank B. T. Kirby for the valuable discussions. Funding. National Science Foundation (2034019-ECCS); U.S. Department of Energy, Office of Science, Advanced Scientific Computing Research (ERKJ378, ERKJ353).