Harnessing the frequency dimension in integrated photonics provides significant advantages such as scalability, noise resilience, and compatibility with telecom technologies. Henry et al. (2023) have advanced this field by developing silicon ring resonators that occupy less than 0.05 mm² yet offer more than 70 frequency channels with a 21 GHz separation. This design facilitates the parallelization and independent control of 34 single qubit-gates, enabling comprehensive characterization of 17 frequency-bin maximally entangled qubit pairs through quantum state tomography. Notably, this technology supported the creation of a fully connected 5-user quantum network in the frequency domain, marking a significant progression toward scalable quantum circuits for quantum computing and secure communications using silicon photonics.

Reference:

• A. Henry et al. (2023). “Parallelization of frequency domain quantum gates: manipulation and distribution of frequency-entangled photon pairs generated by a 21 GHz silicon micro-resonator,” arXiv. Link to article.