# Abstract

Quantum networking, the transfer of quantum information across long distances, has great promise for scaling and interoperating quantum technologies, to allow us to solve problems that would not be possible or feasible classically. Many of the quantum systems that would form the nodes of this network have microwave energy scales, but the most feasible long-distance interconnects are fibre optics transmitting single optical photons. Thus, a means of correlating quantum information between microwave and optical systems is a near-requirement of quantum networking. This requires a hybrid microwave-optical quantum system, which can be used for quantum transduction, direct conversion of microwave and optical photons, and microwave-optical entangled photon pair generation. In this project, I develop numerical models with which to characterise transduction efficiencies and photon pair generation rates in hybrid systems that use ensembles of atoms with both microwave and optical transitions.