Sideband entanglement preparation and their applications in quantum information science

In the field of quantum information science, the development of quantum resources for generating copious entangled photons remains a critical challenge. Leveraging the broad spectral characteristics of the parametric down-conversion process, numerous sideband modes distributed symmetrically around the squeezed light in the frequency domain exhibit quantum noise correlations analogous to Einstein-Podolsky-Rosen (EPR) entanglement, which also termed as sideband entanglement. Owing to their distinct advantages in deterministic entanglement distribution, high-capacity entanglement generation, and high-efficiency detection, continuous-variable entangled sideband modes hold significant promise for applications in quantum information science. In this paper, the development of quantum sideband entanglement and experimental progress over the past two decades are reviewed.