Engineered electron-phonon interaction of negatively charged Silicon-Vacancy center in nanostructured diamond.

纳米结构金刚石中带负电的硅空位中心的工程电子-声子相互作用。

• 批准号: 398628099
• 负责人: Professor Dr. Alexander Kubanek
• 金额: --
• 依托单位: Institut für Quantenoptik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/398628099?language=en
• 关键词: Engineered; electron; phonon; interaction; negatively

The aim of the project is to prolong coherence properties of SiV-center while operating at moderate temperatures of few Kelvin. We pursue two strategies. 1) Employing SiV- center in nanodiamonds (NDs) introduces a cut-off frequency for resonant phonon modes. When working with sizes of a few tens of nanometers phonon frequencies below the relevant fine structure transition will be suppressed. Challenges for this strategy arise from the small size and therefore the proximity of the SiV-center to the diamond surface resulting in photo-instability and spectral-instability. Methods include chemical stabilization of SiV-center in NDs and improvements in ND production process. 2) Since spin relaxation originates from interaction with phonon modes of E point-group symmetry the spin relaxation can be reduced by embedding SiV-centers in nano-mechanical resonators where density of available phonon states is reduced and coupling to E phonon modes that are resonant with fine structure transitions is suppressed. Main advantage compared to SiV- center in NDs is the increased structure size. The emitters are further away from the diamond surface resulting in bulk-like optical properties. Main challenges of this strategy arise from dedicated diamond nano-structuring and fabrication of nano-pillar structures (NPs) of various geometry as well as positioning of SiV-center within phononic mode. With this project, we establish a new quantum emitter with excellent optical properties and long coherence times at moderate temperatures with potential applications in Quantum repeaters, Quantum sensing, or Quantum Information.

该项目的目的是延长 SiV 中心的相干性，同时在几开尔文的中等温度下运行。我们奉行两种策略。 1) 在纳米金刚石 (ND) 中采用 SiV 中心引入了谐振声子模式的截止频率。当使用几十纳米的尺寸时，低于相关精细结构转变的声子频率将被抑制。该策略面临的挑战来自于尺寸小，因此 SiV 中心靠近金刚石表面，导致光不稳定和光谱不稳定。方法包括 ND 中 SiV 中心的化学稳定和 ND 生产工艺的改进。 2) 由于自旋弛豫源自与 E 点群对称的声子模式的相互作用，因此可以通过将 SiV 中心嵌入纳米机械谐振器中来减少自旋弛豫，其中可用声子态的密度降低，并耦合到谐振的 E 声子模式精细结构转变被抑制。与 ND 中的 SiV 中心相比，主要优点是结构尺寸增加。发射器距离金刚石表面更远，从而产生类似块体的光学特性。该策略的主要挑战来自于专用金刚石纳米结构和各种几何形状的纳米柱结构（NP）的制造以及声子模式内 SiV 中心的定位。通过这个项目，我们建立了一种新的量子发射器，在中等温度下具有优异的光学特性和长相干时间，在量子中继器、量子传感或量子信息中具有潜在的应用。