CAREER: Electron-phonon processes in gate-defined silicon quantum dots: measurement, control, and applications.

职业：门定义硅量子点中的电子声子过程：测量、控制和应用。

• 批准号: 2046428
• 负责人: Meenakshi Singh
• 金额: $ 68.56万
• 依托单位: Colorado School of Mines
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2046428&HistoricalAwards=false
• 关键词: CAREER; Electron; phonon; processes; gate

Non-technical abstract: Acting like electrically controllable ‘artificial atoms’, quantum dots are a useful system to study a wide range of condensed matter physics phenomena ranging from bond formation and magnetism to the fundamentals of quantum information. In this project, the research team will study the ubiquitous coupling between electrons and phonons. Of particular interest is the impact of the phonons on the spin of the electrons. Control over the phonon-spin interaction, achieved here via nano-structuring and applied strain, has crucial implications for a number of applications, such as quantum computing. In the course of this project, a new generation of undergraduate and graduate students are being trained with expertise in nanoscale fabrication, cryogenics, and microwave measurements. These skills are relevant to the nationwide calls for a quantum workforce. The research efforts are being integrated with the Microelectronics Processing course at Mines via development of illustrative quantum experiments. Finally, modules are being developed to be incorporated into outreach efforts to middle school children in the Rocky Mountain Camp for Dyslexic Children.Technical abstract: Electron-phonon coupling is ubiquitous in Condensed Matter systems. It plays a pivotal role in relaxation and decoherence (in case of multiple spins) of electronic spin states and is predicted to mediate many-body phenomena. An immense body of research on tailoring it in fields as varied as superconductivity and thermoelectrics exists. Insight from these fields has never been applied to experiments in few-spin systems. This is a new and impactful opportunity, since few-spin systems are the fundamental prototype for rationalizing spin dynamics in more complex systems, important for quantum information applications. This project bridges the gap via an experimental effort focused on control and measurement of electron-phonon processes in silicon gate-defined quantum dots. The phonon bath is engineered through nano-structuring and spin-orbit coupling is controlled via applied strain to investigate the theoretically predicted ‘protected’ states. Measurements of spin relaxation and decoherence time are performed. Controlling the coupling of spins to the phonon bath has profound implications. First, it can be used for the design of ‘hot’ qubits and spintronic devices. Second, it leads to an examination of hitherto untested theoretical predictions. Third, the novel protocols developed in the project for sensing nanoscale electron-phonon thermalization are foundational for future quantum thermodynamics studies on the quantum dot platform. Finally, this is a pioneering effort to apply insight from the vast field of nano-phononics to spin qubits and paves the way for future integration of the fields.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.

非技术摘要：像电控制的“人造原子”一样，量子点是一个有用的系统，用于研究从键形成和磁性到量子信息的基础知识的广泛的凝结物理物理现象。在这个项目中，研究团队将研究电子与声子之间的无处不在的耦合。特别值得关注的是声子对电子自旋的影响。通过纳米结构和应用应变实现的对声子自旋相互作用的控制对许多应用（例如量子计算）具有至关重要的影响。在这个项目的过程中，新一代的本科生和研究生正在接受纳米级制造，低温和微波测量方面的专业知识。这些技能与全国性的量子劳动力有关。通过开发说明性量子实验，研究工作与矿山的微电子处理课程融合在一起。最后，正在开发模块，以纳入落基山山营地的中学儿童的外展工作。技术摘要：电子 - phonon耦合无处不在，在冷凝的物质系统中。它在电子自旋态的松弛和变质（多个自旋）中起关键作用，预计可以介导多体现象。关于在超导性和热电学的各种田野中量身定制它的大量研究。这些领域的洞察力从未应用于几旋链系统中的实验。这是一个新的且有影响力的机会，因为很少的自旋系统是更复杂系统中旋转动力学合理化的基本原型，对于量子信息应用很重要。该项目通过侧重于控制和测量硅栅极定义的量子点的电子 - 光过程的实验工作来弥合差距。声子浴是通过纳米结构进行设计的，并通过施加的应变来控制自旋轨道耦合，以研究理论预测的“受保护”状态。进行自旋松弛和分离时间的测量。控制旋转与声子浴的耦合具有深远的影响。首先，它可用于设计“热”量子和自旋设备的设计。其次，它导致对迄今未经测试的理论预测的检查。第三，该项目在感测纳米级电子phonon热化的项目中开发了新的方案，是量子点平台上未来的量子热力学研究的基础。最后，这是一项开创性的努力，旨在将纳米音波广泛领域的洞察力运用，以旋转数量，并为未来整合该领域的方式铺平道路。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛的影响审查标准来通过评估来通过评估来支持的。