电子旋转放松和集群在高压高温合成的微晶钻石颗粒与减少含量
Nicholas Nunn1,2, Sergey Milikisiyants2, Marco D Torelli1
1Adámas Nanotechnologies, Inc., Raleigh, NC 27617, USA.
概括
减少钻石微粒中的含量显著提高了空 (NV) 旋转连贯性. 将从29ppm降低到3ppm,改善了NV-放松时间,有利于量子传感应用.
科学领域:
- 量子物理学 量子物理学 是一种量子物理学.
- 材料科学 材料科学 材料科学
- 钻石光学 钻石光学 钻石光学
背景情况:
- 钻石中的空 (NV-) 中心对于量子信息和传感至关重要.
- 替代性对于NV-形成至关重要,也会产生偏磁P1中心,降低NV-旋转连贯性.
- 典型的1b型钻石具有高含量 (>100 ppm),影响NV性能.
研究的目的:
- 研究降低含量对高压高温 (HPHT) 合成钻石微粒中的NV-和P1中心自旋特性的影响.
- 确定较低的度是否可以改善NV-传感应用的旋转连贯性.
主要方法:
- 合成HPHT的钻石微粒 (140-185微米) 的表征,含有不同的含量 (3-38 ppm).
- 利用电子磁共振 (EPR),光学检测磁共振 (ODMR) 和核磁共振 (NMR) 来分析旋转特性.
- 在1.2特斯拉的哈恩回声实验中测量了集体NV旋转连贯性.
主要成果:
- 将含量从29ppm降低到3ppm,导致NV-旋转-旋转放松时间增加了3倍 (T2).
- 分析显示,P1中心至少有两个不同的群体 (快速和缓慢的放松旋转).
- 即使在低度 (<10 ppm) 中,也观察到P1中心的异质分布,表明潜在的旋转集群.
结论:
- 含有低的HPHT钻石微粒显示出更好的旋转特性.
- 降低度和相关的P1中心增强NV-spin连贯性.
- 这些发现证明了低HPHT钻石在先进的NV感应应用中的潜力.
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