The unique spin-optical properties of NV defects in SiC, coupled with silicon carbide's advanced technology compared to diamond, make them a promising candidate for quantum technology applications. In this study, using photoinduced pulse ESR at 94 GHz (3.4 T), we reveal the room temperature spin coherence of NV defects in 6H-28SiC, purified to reduce 29Si concentration to ≈1%, four times below its natural level. We demonstrate room temperature (300 K) Hahn-echo coherence time T2 = 23.6 μs, spin–lattice relaxation time T1 = 0.1 ms, and coherent control over optically polarized NV spin states through Rabi nutation experiments. We reveal long inhomogeneous dephasing time T2* = 1.5 μs, which is about five times greater than that measured for NV defects in SiC with natural isotopic content. Our observations highlight again the potential of NV defects in 6H-28SiC, which exhibit near-infrared optical excitation and emission properties compatible with O-band fiber optics, as promising candidates for applications in quantum sensing, communication, and computation.

中文翻译：

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环境条件下同位素富集 6H-28SiC 中 NV 缺陷的相干性


SiC 中 NV 缺陷独特的自旋光学特性，加上碳化硅与金刚石相比的先进技术，使其成为量子技术应用的有前途的候选者。在这项研究中，使用 94 GHz （3.4 T） 的光诱导脉冲 ESR，我们揭示了 6H-28SiC 中 NV 缺陷的室温自旋相干性，纯化后将 29Si 浓度降低到 ≈1%，比其自然水平低四倍。我们证明了室温 （300 K） Hahn 回波相干时间 T2 = 23.6 μs，自旋晶格弛豫时间 T1 = 0.1 ms，以及通过 Rabi 章动实验对光偏振 NV 自旋态的相干控制。我们揭示了较长的非均匀消相时间 T2* = 1.5 μs，这大约是具有天然同位素含量的 SiC 中 NV 缺陷测量值的五倍。我们的观察再次强调了 6H-28SiC 中 NV 缺陷的潜力，它表现出与 O 波段光纤兼容的近红外光学激发和发射特性，是量子传感、通信和计算应用的有希望的候选者。