Electrical Control of Silicon Carbide Cavity QED Systems

Color centers in 4H silicon carbide have recently become an excellent platform for studying quantum information science. The silicon vacancy in 4H silicon carbide is particularly attractive because of its well-studied spin-3/2 level structure, long spin coherence, convenient optical transition wavelength (916 nm), and compatibility with nanophotonic structures [1,2]. A core challenge in building complex spin-photon entangled states with the silicon vacancy is the spectral diffusion and inhomogeneous distribution of individual defect optical frequencies. Theoretical predictions suggest that modulation of an optical cavity containing silicon vacancies can mitigate the effect of spectral diffusion [3]. Recent measurements of the Pockels coefficients in 4H silicon carbide suggest that cavity modulation can be achieved through the electro-optic effect [4], and bulk reduction of spectral diffusion has also been seen via Schottky diodes [5]. Controlling spectral inhomogeneous distributions has also been demonstrated via Stark tuning of individual silicon vacancies in bulk 4H silicon carbide [6]. Here we demonstrate progress towards utilizing electrical control schemes demonstrated in bulk silicon carbide to precisely tune the interaction between silicon carbide vacancies and the optical whispering gallery modes within high quality factor microresonators.

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[2] Park, Jeongeun, et al. Physical Review Applied 21.5 (2024)

[3] Mishra, Sattwik Deb, et al. Physical Review Applied 16.4 (2021)

[4] Wang, Ruixuan, et al. Optics Letters 48.6 (2023)

[5] Steidl, Timo, et al. arXiv preprint arXiv:2410.09021 (2024)

[6] Lukin, Daniil M., et al. npj Quantum Information 6.1 (2020)