SI2-SSE: PERTURBO: A Software for Accelerated Discovery of Microscopic Electronic Processes in Materials

材料的电子、光学和热学性质是由材料内部发生的微小电子碰撞决定的，这些碰撞发生在万亿分之一秒(皮秒)的时间尺度上，因此很难进行实验研究。该项目支持开发一种名为PERTURBO的计算机程序，该程序将用于研究材料中电子的动力学，以期了解电子碰撞。PERTURBO求解控制电子运动的量子力学方程所需的唯一输入是所研究材料的原子结构。此外，PETURBO使用创新的计算技术来高效地求解这些方程。因此，PERTURBO不仅可以用于研究现有材料，还可以用于研究下一代更复杂的材料和设备。PERTURBO在材料上的应用将使电子、照明、能源和其他技术取得颠覆性的进步。此外，国家利益的实验设施，如自由电子激光和其他在基本层面上理解材料的雄心勃勃的实验，迫切需要理论和计算工具来了解微观层面的电子动力学。PERTURBO填补了美国未来科学技术发展所需的科学软件的重要空白，从而服务于NSF的科学使命，并使美国处于材料和设备研究的前沿。最后，该代码将免费提供，用户友好，并广泛使用；用户将包括学术研究团体，国家实验室，和工业。该奖项支持PERTURBO的开发，这是一个强大的软件平台，可以从第一性原理计算材料中电子、声子、缺陷、光子和激子之间的散射过程。PERTURBO的模块化体系结构围绕着计算电子-声子、电子-电子、电子-缺陷和电子-光子散射过程的快速并行例程。该代码采用了新的技术来计算和内插矩阵元素，并收敛这些散射过程的时间标度。PERTURBO从密度泛函理论、密度泛函微扰理论和GW-BSE计算中引入输入，并与程序接口以计算和输出输运性质和超快电子动力学。为了增强易用性，将开发一个Python驱动程序来自动运行计算并分析结果。PERTURBO允许用户定量研究新材料中的电荷、热量和能量传输，包括半导体、绝缘体、金属、纳米结构和界面，以及超快电子和激发态动力学。这些代码填补了当前软件生态系统中的一个主要空白。特别是，它解决了在后摩尔定律电子学时代更深入地了解电子动力学的需要，以及研究对先进的超快时间分辨光谱仪至关重要的超快电子过程。

The electronic, optical, and thermal properties of materials are determined by microscopic electron collisions that take place inside materials on a time scale of a trillionth of a second (a picosecond), and are thus very hard to study experimentally. This project supports the development of a computer program, called PERTURBO, which will be used to study the dynamics of electrons in materials, with a view to understanding electron collisions. The only input needed by PERTURBO to solve the equations of quantum mechanics that control electron motion is the atomic structure of the material under study. In addition, PETURBO use innovative computational techniques to solve these equations efficiently. Thus PERTURBO may be used not just to study existing materials but also to study the next generation of more complex materials and devices. The application of PERTURBO to materials will enable disruptive advances in electronics, lighting, energy, and other technologies. Further, experimental facilities of national interest, such as the free-electron laser and other ambitious experiments to understand materials on a fundamental level, are in critical need of theoretical and computational tools to understand electron dynamics at microscopic levels. PERTURBO fills an important gap in the scientific software needed for the future development of science and technology in the United States, thus serving NSF's science mission, and places the country at the leading edge of materials and device research. Finally, the code will be freely available, user-friendly, and widely usable; users will include academic research groups, national laboratories, and industry.This award supports the development of PERTURBO, a robust software platform to compute from first principles the scattering processes among electrons, phonons, defects, photons, and excitons in materials. The modular architecture of PERTURBO revolves around fast parallel routines to compute electron-phonon, electron-electron, electron-defect, and electron-photon scattering processes. The code employs novel techniques to compute and interpolate the matrix elements and converge the timescale for these scattering processes. PERTURBO imports inputs from density functional theory, density functional perturbation theory, and GW-BSE calculations, and is interfaced with routines to compute and output transport properties and ultrafast electron dynamics. For enhanced usability, a Python driver will be developed to automatically run the calculations and analyze the results. PERTURBO allows the users to quantitatively study charge, heat, and energy transport in novel materials, including semiconductors, insulators, metals, nanostructures, and interfaces, as well as ultrafast electron and excited state dynamics. The code fills​ a major void in the current software ecosystem. In particular, it addresses the need to more deeply understand electron dynamics in the post-Moore's law era of electronics, as well as study ultrafast electronic processes of key importance for advanced ultrafast time-resolved spectroscopies.