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arXiv:2602.06421

Coherent Spin-Photon Interface of single PL6 Color Centers in Silicon Carbide

Zhen-Xuan He, Gergő Thiering, Rui-Jian Liang, Ji-Yang Zhou, Shuo Ren, Wu-Xi Lin, Zhi-He Hao, Qi-Cheng Hu, Jun-Feng Wang, Adam Gali, Jin-Shi Xu, Chuan-Feng Li, Guang-Can Guo

quant-phSubmitted Feb 6, 2026• Announced Feb 9, 2026• 0 citations
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Abstract

The PL6 color center in silicon carbide has recently emerged as a promising platform for quantum information processing, yet its coherent spin--photon interface has remained largely unexplored. Here we present a comprehensive investigation of single PL6 centers, combining spectroscopy with theoretical analysis. The excited-state fine structure is fully resolved using group-theoretical modeling and strain-dependent measurements. Under resonant excitation, we achieve a spin initialization fidelity of $99.69 \pm 0.03\%$ and a readout contrast of $98.31 \pm 1.03\%$. The spin--photon--entangled $A_2$ transition exhibits narrow optical linewidths ($\sim 180$~MHz) and a polarization visibility of $\sim 82\%$. Coherent optical driving enables Rabi frequencies up to $2.895$~GHz, while dynamical decoupling extends the spin coherence time from $0.5$~ms to $5.70$~ms. Our results establish PL6 as a competitive solid-state spin--photon interface hosted in a commercially available semiconductor platform.

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7 pages,4 figures

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