The investigation and control of spin dynamics in semiconductors using ultrafast optical methods

在过去的几年里，世界各地的研究人员一直在追求高性能半导体技术的新方向，包括激光，光子器件，电子逻辑，甚至使用量子信息的新计算机，这些都将基于电子的量子力学性质“自旋”进行操作。凭借这种自旋特性，电子充当了一个微小的磁铁，而基于自旋的半导体器件将通过控制磁铁的方向来工作。由于翻转电子自旋方向比在半导体中使用静电电荷物理移动电子所需的能量要少得多，因此基于自旋的晶体管逻辑将比传统的基于电荷的逻辑器件具有更低的功耗。现在正在开发一类掺杂磁性杂质的新型半导体，其中的电子自旋可以随意排列并使用光来控制。这些材料可以将计算机中的逻辑和记忆功能集成在一起，从而大大简化了计算机的构造方式。半导体量子点是一种半导体嵌入另一种半导体的纳米大小的小块，它为我们提供了一种方便的方法来隔离单个电子。在未来，被困在量子点阵列中的电子的自旋可能使我们能够开发基于量子信息的新型高度安全的通信系统。拟议的资金将支持对新型半导体材料的研究，包括磁性半导体和量子点，这些材料在基于自旋的半导体逻辑、光子学和量子信息领域显示出巨大的应用前景。这些材料将使用一种能产生短脉冲光的特殊激光器进行研究。这些光脉冲可以用来控制自旋方向，并以极高的时间分辨率“读出”这个方向。这个世界级的研究项目将促进加拿大高科技产业的发展，为开发尖端的旋转技术提供知识基础和高技能的研究人员和技术人员。

Over the last few years, researchers around the world have been pursuing a new direction for high-performance semiconductor technologies, including lasers, photonic devices, electronic logic, and even new computers using quantum information, that would all operate based on a quantum mechanical property of the electron called "spin". By virtue of this spin property, an electron acts as a tiny magnet, and spin-based semiconductor devices will work by controlling the magnet's direction. Since it takes significantly less energy to flip the electron spin direction than to physically move electrons around in semiconductors using their electrostatic charge, transistor logic based on spin would have much lower power consumption than traditional charge-based logic devices. A new class of semiconductors doped with magnetic impurities are now being developed in which electron spins can be aligned at will and controlled using light. These materials could allow logic and memory functions in our computers to be integrated, leading to a drastic simplification in the way that computers are built. Semiconductor quantum dots, which are tiny nanometer-sized pieces of one type of semiconductor embedded in another, provide us with a convenient way to isolate a single electron. In the future, the spins of electrons trapped in arrays of quantum dots may allow us to develop new highly-secure communication systems based on quantum information. The proposed funding will support research into novel semiconductor materials, including magnetic semiconductors and quantum dots, that show great promise for applications in the areas of spin-based semiconductor logic, photonics and quantum information. These materials will be studied using a special laser that produces short bursts of light. These pulses of light can be used to control the spin direction and to "read-out" this direction with extremely high time resolution. This world-class research program will promote growth of the high technology industry in Canada by providing the intellectual foundation and highly-skilled researchers and technicians for the development of cutting-edge spin-based technologies.