Defect States of Silicon Allotropes for Quantum Information Science

非技术性描述：该项目的重点是新型硅的设计、合成和结构性能控制，这些硅的晶体结构与微电子技术中使用的传统硅不同。它们正在被研究作为量子信息科学的潜在破坏性材料。要研究的新结构由硅笼的3维网络和硅隧道的2维网络组成，所述硅隧道具有将掺杂剂原子捕获在精确的位点位置中的独特能力，所述精确的位点位置使与硅晶格的相互作用最小化。 被捕获的原子可以充当量子比特，这是存储量子信息的基本元素。这些材料可以克服传统硅所面临的主要障碍，例如由于量子位与硅晶格的相互作用而导致的光耦合和信号衰减的挑战。因此，该项目可以实现光学高效的硅基设备，这是硅社区的圣杯。这项研究通过提供一种新的材料来造福社会，这种材料将彻底改变包括计算机芯片、激光、探测器和电信在内的几个全球技术领域。该项目包括强大而新颖的教育和外展活动，为K-12学生，本科生和研究生以及STEM中代表性不足的群体提供令人兴奋的机会，包括夏季研讨会和实习，本科生的研究经验和社区外展。该项目专注于量子计算和相关应用的材料开发，这是一个吸引新生进入STEM的绝佳机会，为广大学生及其教师（小学，初中，高中），包括丹佛代表性不足和低收入社区，创新设计了新的动手，可出口的活动。这些活动既可以是混合式的，也可以是面对面的。模块还专门针对落基山诵读困难营的学生在所有级别。 技术说明：该项目的重点是推进量子信息科学材料所需的自旋缺陷态的关键特性和控制方面的知识。新型晶体硅同素异形体的固有结构和性质为掺杂剂/量子位提供了精确的间隙位点，沿着具有对热激发的低敏感性、长自旋寿命和退相干时间的潜力，再加上电信波长内的直接带隙。该项目提供了对自旋缺陷的新理解，研究活动可能导致全新的量子信息科学材料。该项目的目标是设计，合成和控制晶体硅同素异形体的结构-性能与间隙掺杂剂（笼或通道内），具有受控的缺陷自旋态，比金刚石硅对热激发和自旋弛豫的敏感性低，以减轻金刚石硅的关键问题，用于革命性的量子信息科学材料。项目范围包括薄膜合成和设计具有不同晶体结构和掺杂剂类型和浓度/位置占用的硅同素异形体，以进行系统的研究，以了解和控制掺杂剂的间隙自旋缺陷态以及结构，光学，电学和量子特性的关系。该项目的途径和方法包括：（i）合成和设计薄膜，以生产具有所需掺杂剂的高相纯度同素异形体;（ii）研究结构（X射线衍射;共焦拉曼;扫描电子显微镜;飞行时间二次电离质谱），光学（光致发光光谱，吸收），和电（iii）使用连续波电子顺磁共振和核磁共振光谱测量自旋缺陷态;（iv）自旋相干性的脉冲电子顺磁共振研究。由于该研究团队在硅同素异形体合成/性质、基本缺陷/掺杂剂科学和基于固态掺杂剂的量子信息科学方法方面的独特专业知识，该项目的革命性发现是可能的。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

Nontechnical description: The project is focused on the design, synthesis, and structure-properties control of novel forms of silicon, which differ in crystal structure from the conventional silicon used in microelectronic technology. They are being investigated as potentially disruptive materials for quantum information science. The novel structures to be investigated are comprised of 3-dimensional networks of silicon cages and 2-dimensional networks of silicon tunnels that have the unique ability to trap dopant atoms in precise site locations that minimize interaction with the silicon crystalline lattice. The trapped atoms can act as qubits, the basic element for storing quantum information. These materials could overcome major hurdles being faced with conventional silicon, like challenges with optical coupling and decay of signal due to interactions of qubits with the silicon lattice. Hence, the project could enable optically efficient silicon-based devices, a holy grail of the silicon community. This research benefits society by providing a new class of materials that would revolutionize several global technological fields including computer chips, lasers, detectors, and telecommunications. The project includes strong and novel education and outreach activities that provide exciting opportunities for K-12 students, undergraduate and graduate students, and underrepresented groups in STEM, including summer workshops and internships, research experiences for undergraduates, and community outreach. With the project focus on materials development for quantum computing and related applications this is an exceptional opportunity to attract new students to STEM, with innovative design of new hands-on, exportable, activities for a broad range of students and their teachers (elementary, middle, high school), including underrepresented and low income communities in Denver. These activities are designed as both hybrid and in-person. Modules also specifically target the Rocky Mountain Dyslexic Camp for students at all levels. Technical description: The project is focused on advancing the knowledge on critical properties and controls of spin-defect states that are needed for quantum information science materials. The inherent structure and properties of novel crystalline silicon allotropes provides precise interstitial sites for dopants/qubits to sit, along with the potential for low sensitivity to thermal excitation and long spin lifetimes and decoherence times, coupled with a direct bandgap within the telecommunications wavelength. The project provides new understanding of spin defects and the research activities could lead to a completely new class of quantum information science materials. The project goals are to design, synthesize, and control the structure-properties of crystalline silicon allotropes with interstitial dopants (inside cages or channels), with controlled defect spin-states with lower sensitivity than diamond Si to thermal excitation and spin relaxation, to mitigate key issues in diamond silicon for revolutionary quantum information science materials. The project scope includes thin film synthesis and design of silicon allotropes with different crystal structures and dopant types and concentrations/site occupation to enable systematic investigations to understand and control the interstitial spin defect states of the dopants and the relations of structure, optical, electrical, and quantum properties. The project approach and methods include: (i) Synthesis and design of thin films to produce high phase purity allotropes with desired dopants; (ii) Investigation of the structural (X-ray diffraction; confocal Raman; scanning electron microscopy; time of flight secondary ionization mass spectrometry), optical (photoluminescence spectroscopy, absorption), and electrical (conductivity and mobility) property-relations; (iii) Measurement of spin-defect states using continuous-wave electron paramagnetic resonance and nuclear magnetic resonance spectroscopy; (iv) Pulsed electron paramagnetic resonance study of spin coherence. Revolutionary discoveries from this project are possible because of the research team’s unique expertise in silicon allotrope synthesis/properties, in fundamental defect/dopant science and in solid-state dopant-based quantum information science approaches.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.