Periodic Reporting for period 1 - PEDESTAL (Photon-photon and spin-spin Entanglement using Diamond-based impurity Elements: Silicon, Tin And Lead)
Reporting period: 2020-09-01 to 2022-02-28
The project aims to investigate novel colour centres incorporated in nanophotonic devices as potential nodes and memory in quantum networks. Success of this project will ensure a feasible route to realising full-scale quantum networks based on integrated spin-photon quantum interfaces hosted by wide bandgap materials. This will help push the frontier of new technologies for communication and distributed computing.
We have three achievements for the first reporting period. Firstly, a theoretical study: we identified an efficient way to create photonic cluster states with engineered connectivity using only a single quantum emitter coupled to proximal nuclear spins. This protocol will prove useful in the later stages of the project for multi-photon experiments. The second achievement is the also the most critical one: we were able to demonstrate all-optical quantum control of the spin of a tin-vacancy colour centre in diamond. This will be the workhorse technique in all operations for the rest of the project. The third achievement is the identification of spin-active colour centres in system material hexagonal boron nitride operational at room temperature. This opens great new opportunities to consider significant feasibility of operation if low temperatures are not necessary to being a quantum node. What is not yet verified is the rest of the properties of this colour centre and work will be carried out in parallel to investigate this.
Having already achieved full coherent spin control of the tin vacancy in diamond, we will push towards photonic indistinguishability next. Once that is achieved, the next step is to combine the two approaches to verify the spin-photon quantum entanglement quality. This step will shed light also to the particular protocol we will choose to implement for spin-spin entanglement.