NSF-ANR:QISE: GANDALF- Microresonators for continuous-variable quantum information

This joint NSF-ANR (France) project will tackle theoretical and experimental studies of multipartite entanglement of optical beams with the aim of demonstrating novel technologies in quantum sensing and quantum communication. Multipartite entanglement can be viewed as “3-body” (or more) quantum correlations and is the key feature of disruptive quantum technologies, first among them quantum computing. On the sensing side, GANDALF aims at generalizing, to multiple beams of light, the measurement sensitivity increase achieved for a single beam of light by the Laser Interferometer Gravitational-wave Observatory (LIGO). On the communication side, GANDALF will enable classically unfeasible multipartite quantum communication protocols such as quantum secret sharing, which encodes secret information in a way that can only be unscrambled by the honest collaboration of all communication partners. The GANDALF team proposes to demonstrate multipartite entanglement both in free-space optics (US) and integrated optics (France) and apply them to quantum sensing and communication protocols which are not realizable by classical physics. These experimental efforts will have different foci: bright beams in on-chip photonics in France, non-Gaussian faint states of light for quantum error correction in the US. Moreover, GANDALF’s theory team will pursue fundamental studies of continuous-variable (i.e., field-encoded) quantum information which will inform both experimental efforts. The ultimate goals of the project are to scale up the number of multipartite entangled beams and to progress toward technology deployment in the field by implementing quantum error correction. This collaborative U.S.- U.K. project is supported by the U.S. National Science Foundation (NSF) and the Engineering and Physical Sciences Research Council (EPSRC) of United Kingdom Research and Innovation (UKRI), where NSF funds the U.S. investigator and EPSRC funds the partners in the U.K. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.