Quantum control of spins in silicon carbide with photons and phonons*

There is a growing interest in exploiting the quantum properties of electronic and nuclear spins for the manipulation and storage of quantum information. Here we focus on recent developments in controlling and connecting individual spins in silicon carbide (SiC) using photons and phonons. We find that defect-based electronic states in SiC [1] can be isolated and optically probed at the single spin level with surprisingly long spin coherence times and high-fidelity control within non-isotopically purified, commercial-grade wafers operating at near-telecom wavelengths. Moreover, a detailed study of the defect spin-photon interface yields efficient quantum control in various polytypes along with near-unity electronic and nuclear polarization, highlighting the potential of SiC for photon-mediated entanglement. In addition, we use Gaussian surface acoustic wave resonators to exploit both the piezoelectric and isotropic phonon dispersion properties of SiC to demonstrate Autler-Townes splittings, mechanically driven Rabi oscillations, and explore spin-strain coupling contributions from all mechanical degrees of freedom, including shear [2]. The spatial confinement of phonons is mapped using a synchrotron-based x-ray diffraction real-space microscopy technique with 25 nm spatial resolution [3]. This work expands the versatility of optically and mechanically driven spins in a material with well-developed device and fabrication capabilities and shows promise towards integrating quantum states with hybrid quantum systems for both control and communication.

[1] D.J. Christle et al. Phys. Rev. X 7, 021046 (2017).
[2] S.J. Whiteley et al., arXiv: 1804.10996 (2018).
[3] S.J. Whiteley et al., arXiv: 1808.04920 (2018).

In collaboration with C.P. Anderson, A. Bourassa, S.L. Bayliss, D.J. Christle, A. L. Crook, C.F. de las Casas, F.J. Heremans, M.V. Holt, K.C. Miao, S.J. Whiteley, and G. Wolfowicz.