Magnetically-Doped III-V Semiconductor Nanostructures

磁掺杂 III-V 族半导体纳米结构

• 批准号: NE/T014792/1
• 负责人: Richard Curry
• 金额: $ 1.17万
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FT014792%2F1
• 关键词: Magnetically; Doped; III; Semiconductor; Nanostructures

EPSRC : Daniel Blight : EP/R513131/1As the size of silicon transistors and other circuit features is approaching their physical limits, performance growth has begun to lag behind Moore's law with the time between the introduction of new process nodes increasing and the cost-effectiveness of these nodes decreasing. Two key challenges exist relating to this: (i) the increasing heat generated within silicon chips as more transistors and other devices are added and the difficulty in extracting this heat, and (ii) length scales in the devices are reaching the limit at which quantum effects become dominant and lead to a breakdown of the device performance.As a result there has been much research into alternative technologies that could help to maintain the historical rate of device performance growth. One field that has shown great promise in that area is the field of spintronics, where the spin of electrons is used as another degree of freedom, adding new capabilities to devices. Spin is a quantum mechanical property and charge carriers (e.g. electrons) possess a spin that is defined as either 'up' or 'down'. This property is not the same as the rotating spin of a coin for example which is either clockwise or anti-clockwise, as quantum mechanics allows the electron to carry both 'up' and 'down' at the same time until a measurement is made. This offers the opportunity to utilise this property to perform complex calculation not feasible by current technologies, whilst also enabling the additional storage of information. Importantly, spins can be 'passed' through a material without needing to establish an electrical current. Such spin currents therefore do not generate heat through the effect of resistance (described by Ohm's law) and therefore may offer a solution to the issue of heat generation in devices.Research into materials which are able to display spin properties and transfer etc. has been the focus of much attention as a result for a number of decades. One important feature of spin is that it interacts with magnetic fields and hence the doping of materials with magnetic dopants (such as manganese) to enhance their properties has been undertaken. This has shown some impressive results at low temperatures, however the effect of heat when at room temperature (or above) typically means these effects are 'lost'.To overcome this issue, with the aim of generating materials which operate at room temperature, recent work has indicated that in small structures (nanoscale) the effect of physically confining charge carriers in a structure close to their 'wavelength' can enhance interactions such that they may be observed at higher temperatures. However, the task of doping such small structures with magnetic dopant is very challenging. This project will combine the world-leading expertise in Toronto in generating nanowire materials with the development of a new materials doping capability at Manchester that enables single ions (atoms) to be doped into nanostructures. This will provide a new route to addressing this goal of developing materials suitable for realising room-temperature spin-based devices. It will also offer the opportunity to study quantum effects which in the future might offer an alternative technology to traditional semiconductor electronics (e.g. quantum computing).The placement will provide the opportunity for a PhD student (Daniel Blight) at the University of Manchester to spend an extended period of time at the University of Toronto to develop the protocols for nanomaterials growth, device fabrication, magnetic doping, and characterisation. The placement will form the basis of a much larger collaboration between the groups and Universities involved and be used as a basis for future funding applications, joint PhD studentships and the fluid exchange of researchers between the groups with minimal barriers to accessing world-leading expertise and experimental capabilities.

EPSRC：丹尼尔·布莱特：EP/R513131/1随着硅晶体管和其它电路特征的尺寸接近其物理极限，性能增长已经开始落后于摩尔定律，随着新工艺节点的引入之间的时间增加和这些节点的成本效益降低。在这方面存在两个关键挑战：（i）随着增加更多的晶体管和其它器件而在硅芯片内产生的热量增加以及提取该热量的困难，以及（ii）器件中的长度尺度正在达到量子效应占主导地位并导致器件性能崩溃的极限。因此，已经有许多关于替代技术的研究，这些技术可以帮助维持设备性能增长的历史速度。自旋电子学领域在该领域显示出巨大的前景，其中电子的自旋被用作另一个自由度，为设备增加了新的功能。自旋是量子力学性质，并且电荷载流子（例如电子）具有被定义为“向上”或“向下”的自旋。这种性质与硬币的旋转（例如顺时针或逆时针）不同，因为量子力学允许电子同时进行“向上”和“向下”，直到进行测量。这提供了利用该属性来执行当前技术不可行的复杂计算的机会，同时还实现了信息的附加存储。重要的是，自旋可以“通过”材料，而无需建立电流。因此，这种自旋电流不会通过电阻效应（由欧姆定律描述）产生热量，因此可以为器件中的热量产生问题提供解决方案。因此，对能够显示自旋特性和转移等的材料的研究几十年来一直是人们关注的焦点。自旋的一个重要特征是它与磁场相互作用，因此用磁性掺杂剂（如锰）掺杂材料以增强其性能。这在低温下显示了一些令人印象深刻的结果，然而，在室温下，为了克服这个问题，为了产生在室温下工作的材料，最近的研究表明，在小结构中，（纳米级）在接近其“波长”的结构中物理限制电荷载流子的效果可以增强相互作用，使得它们可以在更高的温度下被观察到。然而，用磁性掺杂剂掺杂这种小结构的任务非常具有挑战性。该项目将联合收割机结合世界领先的专业知识在多伦多在产生纳米线材料与开发一种新的材料掺杂能力在曼彻斯特，使单离子（原子）掺杂到纳米结构。这将为实现这一目标提供一条新的途径，即开发适用于实现室温自旋器件的材料。它还将提供研究量子效应的机会，未来可能会为传统半导体电子学提供替代技术（例如量子计算）。该职位将为博士生提供机会（丹尼尔布莱特）在曼彻斯特大学花了很长一段时间在多伦多大学开发纳米材料生长，器件制造，磁性掺杂的协议，和表征。该职位将成为相关团体和大学之间更大规模合作的基础，并用作未来资金申请，联合博士生奖学金和团体之间研究人员的流体交换的基础，以最小的障碍获得世界领先的专业知识和实验能力。