Acoustically induced electron spin transport in galium arsenide

在固态电子学中利用电子自旋的自旋电子学领域正经历着巨大的兴趣热潮。使用电子的自旋来表示0和1逻辑比特有望产生更快、更高效的自旋电子器件，并最终形成量子计算机的基础。要实现这些目标，有效地传输和操纵电子自旋的基本材料系统和装置是必要的。以前的半导体研究通常讨论的是自旋的传输几乎不能控制其微观运动，或者使用量子点来限制和操纵自旋的局部，而不是限制传输。我的研究将集中在使用动态量子点的独特系统的自旋传输的研究上。动态量子点是由表面声波产生的静态势和动态压电势相结合而产生的。表面声波是在样品表面传播的瑞利波，引起一个点电子自旋可以被限制在动态量子点内，并可以长距离相干传输。为了研究传输过程中的自旋弛豫机制，目标有两个领域。第一个领域的研究将包括通过监测自旋产生的局部磁场来研究每个点中大量的电子自旋(大约100个自旋)。第二个领域将专注于在每个动态量子点内实现单个电子的传输，以便产生以与表面声波频率(大约1 GHz)相当的重复频率运行的单光子发射器。这个项目特别有趣，因为高频单光子发射器将非常适用于有关量子密码学的工作。利用移动限制势实现电子自旋的输运将为发展自旋电子器件和加强加拿大的自旋电子学研究做出重要贡献。

The field of spintronics, which exploits the spin of an electron in solid state electronics, is experiencing a tremendous surge in interest.  Using the spin of the electron to represent the 0 and 1 logic bits is expected to produce faster, more efficient spintronic devices and ultimately form the basis of a quantum computer.  To achieve these goals, basic material systems and devices that efficiently transport and manipulate electron spins are necessary.  Previous studies in semiconductors have typically discussed either the transport of spins with little control of their microscopic movement or the use of quantum dots to confine and manipulate the spins locally at the expense of limiting transport.  My research will centre around the study of spin transport using the unique system of dynamic quantum dots.  Dynamic quantum dots are created by the combination of static potentials with a dynamic piezoelectric potential generated by surface acoustic waves.  Surface acoustic waves are Rayleigh waves that travel on the surface of a sample causing a point on the surface to move in both the vertical and longitudinal directions.  Electron spins can be confined within the dynamic quantum dots and coherently transported over long distances.  To study the spin relaxation mechanisms during transport, two areas are targeted.  In one area, the research will include the study of a large number of electron spins (on the order of 100 spins) in each dot by monitoring the local magnetic field generated by the spins.  The second will focus on enabling the transport of a single electron within each dynamic quantum dot in order to produce a single photon emitter that operates at repetition rates comparable to the surface acoustic wave frequency (approximately 1 GHz).  This project is particularly interesting because a high frequency single photon emitter would be very applicable to work regarding quantum cryptography.  In both research areas, the transport of electron spins using mobile confinement potentials will provide an important contribution to the development of spintronic devices and strengthen spintronics research in Canada.