CAREER: First-principles calculations of quantum processes in bulk and nanostructured semiconductors

点击翻译按钮获取中文摘要

TECHNICAL SUMMARYThis CAREER award is made on funds from the Division of Advanced Computing Infrastructure and the Division of Materials Research. It supports an integrated research and educational program on the theoretical study of quantum processes in materials using first-principles computational methods. Quantum processes play a crucial role in the operation and efficiency of modern electronic, optoelectronic, photovoltaic, and thermoelectric devices. Theoretical studies can provide insight into the microscopic mechanisms that govern quantum processes in materials but are inaccessible to experiment. First-principles methods based on density functional theory enable the predictive calculation of the electronic properties of materials entirely from theory, without empirical or adjustable parameters.This research program will focus on quantum processes in technologically important bulk and nanostructured semiconducting materials. The role of scattering mechanisms such as carrier-phonon and carrier-carrier coupling will be explicitly evaluated with density-functional and many-body perturbation theory, respectively. In combination with the Boltzmann equation formalism, these studies will provide valuable insight on the nature and significance of microscopic quantum processes during carrier transport in devices. Studies of optical absorption by free carriers and nonradiative Auger recombination will elucidate the microscopic nature of these parasitic quantum processes and their role in the operation and efficiency of optoelectronic devices.The research program will be integrated with educational activities through the incorporation of numerical calculations and computer simulations in the undergraduate and graduate curriculum and the training of graduate and undergraduate students. Proposed outreach activities aim to assist students from community colleges in making the transition to Engineering at the University of Michigan. The effectiveness of the educational program will be evaluated by education professionals at the Center of Research on Learning and Teaching at the University of Michigan. Computer codes for the predictive theoretical calculation of quantum processes will be created and shared with the educational and research communities with the intent to contribute to software reuse and the software cyberinfrastructure of the materials research community.NONTECHNICAL SUMMARYThis CAREER award is made on funds from the Division of Advanced Computing Infrastructure and the Division of Materials Research. It supports an integrated research and educational program on the theoretical study of quantum phenomena in materials with predictive computational methods. Semiconductor devices have significant impact on modern society and improve our quality of life. For example, transistors are the fundamental components of computers that are a cornerstone of the Information Age. Semiconductor lasers enable high-speed fiber-optics communications, while light-emitting diodes are novel light sources that can replace incandescent and fluorescent light bulbs. Solar cells are used to produce electricity from sunlight, while thermoelectric devices can convert heat directly into electricity and power deep-space probes such as the NASA Curiosity rover on Mars. The motion of electrons in the underlying semiconducting materials, described by the laws of quantum mechanics, lies at the foundations of how these devices operate.The goal of this research program is to develop and apply predictive computational tools in order to understand the properties in semiconducting materials related to the transport of electrons through the material. This work will focus on how the motion of electrons is affected by their interactions with each other and with atomic vibrations. This study will also focus on how certain quantum processes cause energy loss in semiconductor devices. The results obtained from this work will assist in the development of better-performing and energetically more efficient semiconductor devices.The research program will be integrated with educational activities through the incorporation of numerical calculations and computer simulations in the undergraduate and graduate curriculum and the training of graduate and undergraduate students. Proposed outreach activities aim to assist students from community colleges in transitioning to Engineering at the University of Michigan. The effectiveness of the educational program will be evaluated by education professionals at the Center of Research on Learning and Teaching at the University of Michigan. Computer codes for the predictive theoretical calculation of quantum processes will be created and shared with the educational and research communities with the intent to contribute to software reuse and the software cyberinfrastructure of the materials research community.