Van der Waals materials for integrated nanophotonics

Integrated quantum photonics is pivotal for the implementation of quantum technologies and their transition from a laboratory to a real-life context. The building blocks of a photonic circuit may comprise one or more single photon emitters (SPEs) and diverse components, such as waveguides, beam splitters, interferometers etc. required for steering and processing the quantum signals produced by the sources. In order to minimise the circuit size and energy consumption, photonic circuits should integrate as many components as possible on a same chip. Currently, it is extremely challenging finding a single material that can be used both as SPE and medium in which the single photons are transmitted. The long-term vision of VALERIA is the achievement of a single-material platform for the realisation of on-chip photonic quantum devices exploiting the nanostructurisation of van der Waals crystals. Our final goal will be the fabrication of a device made of a single non-centrosymmetric transition metal dichalcogenide bulk crystal embedding site-controlled SPEs deterministically integrated with photonic crystal cavities and coupled to electric-field configurable waveguides/beamsplitters.