Towards an efficient spin-photon interface based on tin-vacancy centres in diamond nanophotonic devices

Colour centres in diamond are promising candidates for the realisation of quantum network nodes, thanks to their good optical and spin coherence properties. High-precision quantum control over the NV centre has enabled milestone experiments in quantum science, but the NV’s susceptibility to charge noise hinders large-scale on-chip integration. The tin-vacancy (SnV) centre recently emerged as a resourceful alternative platform thanks to its improved optical properties, the second-long relaxation times expected around 1K and compatibility with nanophotonic integrated devices, thanks to the first-order insensitivity to electric field fluctuations arising from its symmetry properties. Together with the recent developments in diamond nanofabrication techniques and hybrid integrated photonics, this makes the SnV interesting for realising scalable platforms and on-chip devices.

Here we report on fabrication of single SnV centres in diamond and characterisation of their optical and spin coherence properties. Furthermore, we present our work towards realising an efficient spin-photon interface based on SnV centres integrated in all-diamond nanophotonic devices, with the goal of using it as building block for quantum network applications.