Ultrafast Optical Studies of Semiconductor Materials for Spintronics and Quantum Computing

由该发现基金支持的研究项目涉及研究和控制新型半导体材料的快速过程，这些材料在先进技术（磁敏逻辑、光电子和量子信息）中具有强大的应用潜力。我们的实验都使用特殊的激光器，产生持续时间约为100飞秒的短脉冲光。为了更好地理解这个时间尺度，将100飞秒与1秒进行比较，相当于将1厘米与地球与太阳之间的距离进行比较。这些所谓的超快激光脉冲可用于研究极快的事件，如固体中电子的运动。我们研究的主要目标是在两类材料中追求超快光学控制：(i)稀释磁性半导体；（二）半导体量子点。稀释磁性半导体是掺杂磁性原子的传统半导体。这些材料可能会改变我们制造计算机的方式，使逻辑和存储功能相结合，以及光互连和交换的结合，从而使计算机具有更低的功耗和更高的速度。我们的团队正在使用超快激光技术开发基于这些材料的光寻址磁存储元件。半导体量子点是一种半导体在另一种半导体的三维矩阵内的微小（纳米大小）区域。这些微小的区域（点）可以用来捕获单个电子，并在固态量子计算机中充当“量子比特”，有望在高功率计算、密码学和许多其他重要领域取得进展。我们研究的目标之一是使用超快脉冲进行计算，这将使这样的计算机速度极快，并允许在退相干（这会破坏量子信息）开始之前进行计算。通过在这些前沿科学和技术领域的广泛知识基础的发展，以及对光子学和半导体行业高技能研究人员的培训，拟议的研究计划将为加拿大带来宝贵和持久的利益。

The research program supported by this Discovery Grant involves the study and control of fast processes in novel semiconductor materials that have strong potential for applications in advanced technology (magneto-sensitive logic, opto-electronics and quantum information). Our experiments all utilize special lasers that produce short pulses of light with a duration of about 100 femtoseconds. In order to put this time scale into perspective, comparing 100 femtoseconds to 1 second is equivalent to comparing 1 centimeter to the distance between the earth and the sun. These so-called ultrafast laser pulses may be used to study extremely rapid events, such as the motion of electrons in solids. The primary objective of our research is the pursuit of ultrafast optical control in two classes of materials: (i) diluted magnetic semiconductors; and (ii) semiconductor quantum dots. Diluted magnetic semiconductors are traditional semiconductors doped with magnetic atoms. These materials may change the way we build computers, allowing logic and memory functions to be combined as well as the incorporation of optical interconnects and switching, leading to computers with lower power consumption and higher speed. Our group is using ultrafast laser techniques to develop optically-addressable magnetic memory elements based on these materials. Semiconductor quantum dots are tiny (nanometer-sized) regions of one type of semiconductor inside a 3D matrix of another semiconductor. These tiny regions (the dots) may be used to trap individual electrons and act as "quantum bits" in a solid state quantum computer, promising advances in high power computing, cryptography, and many other important areas. The use of ultrafast pulses for computation, one of the goals of our research, would make such a computer extremely fast and allow computations to be carried out before decoherence (which destroys the quantum information) sets in. Through the development of a broad-based foundation of knowledge in these cutting-edge areas of science and technology, together with the training of highly-skilled researchers for the photonics and semiconductor industries, the proposed research program will have valuable and lasting benefits to Canada.