Spintronics and Quantum Information Processing with 1D Ge/Si Nanowires

本研究的目标是实现基于半导体纳米线的新型电子器件，包括基于自旋的场效应晶体管和量子超导晶体管，并探索基于固态的量子信息处理方案。该方法是基于一个干净的一维空穴气体系统中形成的化学合成，分子大小的锗/硅纳米线。长的平均自由程、沿着的可调应变和空穴气系统中的量子限制效应提供了独特的潜力，包括长的自旋弛豫长度和栅极可控的自旋-轨道耦合效应。将探索将自旋电注入半导体系统。还将研究基于耦合量子点中载流子自旋的量子比特。读出的最终量子位状态将实施与自旋电荷转换计划使用射频单电子晶体管作为charge sensor.Intellectual MeritThis研究，由于其独特的组合自旋电子学，量子信息处理，控制纳米结构的生长，并利用技术上重要的第四族材料，很可能会有显着的广泛影响社会。这里开发的自旋电子器件和量子比特将为社会提供新的计算和密码学手段，并影响包括电气工程，物理和化学在内的众多领域。与此同时，在研究过程中获得的知识将使人们深入了解自旋动力学和量子力学的基本理解。更广泛的影响最后，本提案中所述活动的研究部分将与本科生和研究生教育以及旨在扩大拟议研究影响的其他活动密切相关。

The objective of this research is to realize novel electronic devices based on semiconductor nanowires, including spin based field-effect transistors and quantum supercurrent transistors, and to explore solid-state based quantum information processing schemes. The approach is based on a clean one-dimensional hole gas system formed in chemically synthesized, molecular size germanium/silicon nanowires. The long mean free path, along with tunable strain and quantum confinement effects in the hole gas system offer unique potential including long spin relaxation length and gate controllable spin-orbit coupling effects. Electrical injection of spin into the semiconductor system will be explored. Qubits based on carrier spins in coupled quantum dots will also be studied. Read-out of the final qubit state will be implemented with a spin-charge conversion scheme using a radio-frequency single-electron transistor as the charge sensor.Intellectual MeritThis research, due to its unique combination of spintronics, quantum information processing, controlled growth of nanostructures, and utilization of technologically important group IV materials, is likely to have significant broad impact for society. The spintronics devices and qubits developed here will provide the society with new means of computation and cryptography, and affect numerous fields including electrical engineering, physics and chemistry. In the meantime, the knowledge gained during research will give insight into basic understanding of spin dynamics and quantum mechanics. Broader ImpactFinally, the research component of the activities described in this proposal will be closely tied to education at both the undergraduate and graduate student level, and other activities intended to broaden the impact of the proposed research.