CANCELLED

Special CPM Seminar

Phonon networks with SiV centers in diamond waveguides

Marc-Antoine Lemonde

Atominstitut
TU Wien

In this talk, I will describe the implementation and operation of a solid-state quantum network, where separated silicon-vacancy (SiV) centers are coupled via the phonon modes of a quasi-1D diamond waveguide. In this setup, quantum states encoded in long- lived spin degrees of freedom can be converted into propagating phonon wavepackets and be reabsorbed efficiently by a distant defect center. Our analysis shows that under experimentally achievable conditions, this approach enables the implementation of high- fidelity and scalable quantum communication protocols within chip-scale spin-qubit networks. Apart from quantum information processing applications, this setup provides a novel waveguide QED platform, where strong-coupling effects between solid-state defects and individual propagating phonons can be explored at the quantum level. Before describing the state transfer protocol, I will motivate the investigation of SiV centers; focusing mainly on the strong strain coupling between their electronic ground states and their environment. In this context, I will briefly describe another application where a single SiV defect can be used to engineer an effective coupling between low- frequency mechanical bending modes and high-frequency compression modes of its host crystal. Therefore enabling laser-cooling-like effect for the low-frequency mechanical vibrations, where the high-frequency compression modes serve as an intrinsic low- temperature reservoir.