Theory and modeling of electro-thermal transport in nanoscale materials and devices

半导体电子塑造了我们的世界。设备尺寸的缩小使这成为可能，这不仅带来了巨大的技术挑战，也提出了许多基本问题。随着时间的推移，人们对纳米级电子传输的深刻理解已经得到了发展，同时也有了精确捕捉相关物理现象的计算工具。原则上，电子传递不能与声子（热）传递分开。耦合电子-声子输运的物理特性导致纳米级器件的自热，这严重限制了它们的性能和可靠性，并为纳米结构中增强热电能量转换提供了一条途径。这些和其他挑战对能源和21世纪的电子产品有着深远的影响。进一步的进展将需要对纳米尺度的热输运有更深入的了解，同时需要开发新的计算工具来平等地对待电子和声子，解决从纳米到宏观尺度的挑战，并与预测第一原理材料建模紧密相关。******这项研究计划的使命是通过创新的理论和建模，推进纳米材料和器件的电热传输的科学和工程。具体的研究重点包括：1)研究纳米尺度上的非平衡电子-声子传输/相互作用，如纳米器件的自加热、纳米尺度上的声子传输和非线性热电转换。2)探索超越传统材料范围的具有独特性能的二维材料和器件。3)开发最先进的从头算量子理论模型，预测材料和器件的电热输运特性，跨越原子到器件的层次结构，并解决超出当前技术范围的更广泛的问题。******这个程序将提供对耦合电子-声子输运的物理学的见解，在纳米尺度上的非平衡现象可能会出现。开发创新的第一性原理多物理场模拟工具将有助于探索新兴材料和器件，解释实验，并加速创新。我们的研究成果将解决重要的挑战，实现更高性能和更低功耗的电子产品，用于高效能量收集和固态冷却的先进热电器件，以及二维材料的新兴应用。该计划将有利于电子，能源，通信，汽车和航空航天工业中使用的技术，其中电子和声子之间的相互作用是重要的

Semiconductor electronics has shaped our world. The downscaling of device dimensions that made this possible not only presented enormous technological challenges, it also raised many fundamental questions. Over time a deep understanding of electron transport at the nanoscale has been developed, along with the computational tools to accurately capture the relevant physics. Electron transport cannot, in principle, be separated from phonon (thermal) transport. The physics of coupled electron-phonon transport is responsible for self-heating in nanoscale devices, which critically limits their performance and reliability, and for providing a route for enhanced thermoelectric energy conversion in nanostructures. These and other challenges have far-reaching implications for energy and 21st century electronics. Further progress will require a deeper understanding of thermal transport at the nanoscale, along with the development of new computational tools that treat electrons and phonons on equal footing, address challenges from the nano- to macro-scale, and that are tightly connected to predictive first principles materials modeling. ******The mission of this research program is to advance the science and engineering of electro-thermal transport in nanoscale materials and devices, through innovative theory and modeling. Specific research thrusts include: 1) Investigating out-of-equilibrium electron-phonon transport/interaction at the nanoscale, such as self-heating in nanodevices, phonon transport on the nanoscale, and non-linear thermoelectric conversion. 2) Exploring 2D materials and devices with unique properties beyond the scope of traditional materials. 3) Developing state-of-the-art ab initio quantum theoretical modeling that predicts the electro-thermal transport characteristics of materials and devices, spans the atoms-to-devices hierarchy, and addresses a broader class of problems beyond the scope of current techniques.******This program will provide insights into the physics of coupled electron-phonon transport, where nonequilibrium phenomena on the nanoscale can arise. The development of innovative first principles multi-physics simulation tools will help explore emerging materials and devices, explain experiments, and accelerate innovation. Our research findings will address important challenges, enabling higher-performance and lower-power electronics, advanced thermoelectrics for efficient energy harvesting and solid-state cooling, and emerging applications for 2D materials. This program will benefit technologies used in the electronics, energy, communications, automotive and aerospace industries, where the interplay between electrons and phonons is important.**