Spin Seebeck Devices for Thermoelectric Power Generation

用于热电发电的旋转塞贝克装置

• 批准号: 1407650
• 负责人: Ashutosh Tiwari
• 金额: $ 25.5万
• 依托单位: University of Utah
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-15 至 2020-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1407650&HistoricalAwards=false
• 关键词: Spin; Seebeck; Devices; Thermoelectric; Power

The development and understanding of sustainable, "green" technologies has been a dominant, driving force for research and commercialization over the last several years. One such technology is thermoelectric power generation, which can be used to convert the ambient heat present in our day-to-day environment into useful electric power. These thermoelectric power generators have potential to drive low powered sensors in variety of remote applications such as monitoring the structural health of bridges, security systems, medical diagnostics, etc. However, presently available thermoelectric power generators exhibit very low heat-to-electricity conversion efficiencies. The proposed project proposes to improve the efficiency of these generators by using the spin of electrons. The fundamental limitations which affect traditional hermoelectric device efficiencies do not apply for these devices. Therefore, spin-based generators can in principle be significantly more efficient than the traditional devices. If successful, the research outcomes will help in reducing greenhouse gas emissions and benefit the society at large. Graduate students and undergraduate students from various disciplines will be provided with learning opportunities within this project. Special efforts will be made to encourage the participation of female and underrepresented minority students in the program. The goal of this project is to enable a new class of energy harvesting devices by utilizing the recently discovered phenomena of the spin Seebeck effect (SSE) and the inverse spin Hall effect. The SSE refers to the generation of a spin voltage in a magnetic material when it is placed in a temperature gradient. The proposed research is based on the hypothesis that this thermally generated spin voltage can be converted into an electrical voltage using the inverse spin Hall effect. Making use of these two effects, in preliminary studies, PI's group has demonstrated the feasibility of designing a room temperature spin-current driven thermoelectric generator that employs a thin film of a magnetic insulator and a high spin-orbit coupled metal, directly coated on a non-magnetic substrate. The above demonstration opens a path to crafting an entirely new class of energy harvesting technologies. However, at present the efficiency of SSE devices is much lower than the traditional thermoelectric devices. For any practical application, efficiency of these devices needs to be enhanced. In this project, PI is proposing to perform in-depth scientific investigations to achieve the above goal. The proposed approach is four-fold: (a) Understanding the mechanism of spin wave transport in magnetic insulators, (b) Enhancing the thermally driven spin-current at the magnetic insulator/normal metal interface by improving the spin mixing conductance (c) Discovering metals with large spin-Hall angles, (d) Device fabrication and optimization.

在过去几年中，对可持续的“绿色”技术的开发和理解一直是研究和商业化的主导驱动力。其中一种技术是热电发电，它可以用来将我们日常环境中存在的环境热量转化为有用的电力。这些热电发电机有潜力驱动低功率传感器在各种远程应用，如监测桥梁，安全系统，医疗诊断等的结构健康，然而，目前可用的热电发电机表现出非常低的热-电转换效率。拟议的项目建议通过使用电子的自旋来提高这些发电机的效率。影响传统热电装置效率的基本限制不适用于这些装置。因此，基于自旋的发电机原则上可以比传统设备更有效。如果成功，研究成果将有助于减少温室气体排放，造福整个社会。来自不同学科的研究生和本科生将在本项目中获得学习机会。将作出特别努力，鼓励女性和代表性不足的少数民族学生参加该方案。该项目的目标是通过利用最近发现的自旋塞贝克效应（SSE）和逆自旋霍尔效应现象来实现一类新的能量收集设备。SSE指的是当磁性材料置于温度梯度中时在磁性材料中产生自旋电压。所提出的研究是基于这样的假设，即这种热产生的自旋电压可以转换成电压使用逆自旋霍尔效应。利用这两种效应，在初步研究中，PI的小组已经证明了设计室温自旋电流驱动热电发电机的可行性，该发电机采用磁性绝缘体和高自旋轨道耦合金属的薄膜，直接涂覆在非磁性基底上。上述演示开辟了一条打造全新能源收集技术的道路。然而，目前SSE器件的效率远低于传统的热电器件。对于任何实际应用，需要提高这些设备的效率。在这个项目中，PI建议进行深入的科学调查，以实现上述目标。所提出的方法是四重的：（a）理解的机制，自旋波输运在磁性绝缘体，（B）增强热驱动的自旋电流在磁性绝缘体/正常的金属界面，通过提高自旋混合电导，（c）发现大自旋霍尔角的金属，（d）设备的制造和优化。