Wafer-scale electrically tunable quantum nodes in silicon carbide*

Defect spin qubits in silicon carbide (SiC) with associated nuclear spin quantum memories [1] can leverage near-telecom emission and wafer-scale semiconductor device engineering [2] for creating quantum technologies. Here, we highlight recent advances with the neutral divacancy (VV⁰) in SiC within the context of long-distance quantum communication and repeater schemes. We isolate single VV⁰ defects in functional SiC optoelectronic devices, which allows for deterministic charge state control and terahertz tuning, but also surprisingly eliminates spectral diffusion in the optical structure of these defects. This results in lifetime-limited single-photon emission through semiconductor depletion which offers a generalizable strategy for quantum emitters limited by charge noise. We further discuss the outlook for electrical control, manipulation, and readout of both the spin and charge degrees of freedom in these spin qubits. Combined with the entanglement and control of nuclear spin registers, this work establishes a promising platform for quantum science.

References:
[1] A. Bourassa* and C. P. Anderson* et al., Nature Materials (2020) [arXiv:2005.07602]
[2] C. P. Anderson* and A. Bourassa* et al., Science 366, 6470, 1225-1230 (2019)