Photonic Quantum Computing via Graphene Nanostructures

US AirForce FA8655-20-1-7030


Project Abstract

The harnessing of quantum physical phenomena will lead to quantum technology that dramatically outperforms its classical counterpart. Among many physical architectures, single photons and their intrinsic advantage of being mobile are the best choice when considering communication tasks or computations where the information must be delegated to distant quantum nodes. However, many data processing operations, such as quantum computer gates, require that individual photons interact strongly. This is a remaining challenge whose solution would benefit a variety of information technologies, reaching from optimal performances of telecom devices to enabling scalable photonic quantum technologies.

This research project will pursue a new approach to achieve this single-photon nonlinear optics, where graphene as a novel monolayer of carbon atoms mediates a nonlinear interaction between two photons. This approach will be based on the remarkable properties of graphene, in which surface plasmons, i.e. photons that have been bound to electrons in a material, can be confined to scales that are millions of times smaller than the photon, inducing exceptionally strong nonlinear interactions. While it has been theoretically shown that nanostructured graphene provides this confinement, allowing single photons to activate nonlinear processes, much remains to be done experimentally.

The main research goal of this project will be the characterization of the nonlinearity of graphene in the classical regime, and then to push it to the single-photon level. The final aim is to create a quantum device that can generate quantum states of light using nanostructured graphene. In addition to finding a host of applications in classical information technology, this project will lay the foundation for a new paradigm of photonic quantum computing based on graphene plasmonics.