Experimentally finding dense subgraphs using a time-bin encoded Gaussian boson sampling device

Understand

Gaussian Boson Sampling (GBS) is a quantum computing concept based on drawing samples from a multimode nonclassical Gaussian state using photon-number resolving detectors.

• It was initially posed as a near-term approach aiming to achieve quantum advantage, but several applications have been proposed ever since, such as the calculation of graph features or molecular vibronic spectra, among others.
• For the first time, we use a time-bin encoded interferometer to implement GBS experimentally and extract samples to enhance the search for dense subgraphs in a graph.
• Our results indicate an improvement over classical methods for subgraphs of sizes three and four in a graph containing ten nodes.