Studies of electronic excitations in functionalized semiconductor materials

Yale University, New Haven CT

Investigators

Abstract

This project continues the development of computational methods to study electronic excitations in semiconductor nanostructures. Fully atomistic simulations will investigate ultrafast quantum dynamical phenomena and coherent control of photoinduced electronic excitations in TiO2, SnO2 and ZnO surfaces functionalized with molecular adsorbates for solar energy conversion. The projects include the characterization of electron-hole pair separation and recombination pathways, photoexcitation methods for laser manipulation of electronic excitations, photoinduced electronic dynamics and trapping mechanisms, and the integration of the proposed research with an outreach educational program for minority students and collaborations with research groups in South America. Intellectual Merit: These studies of quantum electronic relaxation, control and rectification of interfacial electron transfer in fully atomistic models of functionalized semiconductors combine rigorous computational approaches based on large-scale ab initio molecular dynamics and nonequilibrium Green?s function (NEGF) methods as well as direct comparisons with a wide range of experiments. Broad Impact: Studies of quantum dynamics in semiconductor nanostructures will impact a wide range of applications in molecular electronics, photooptic devices, imaging and memory units, as well as photocatalysis, electrochemistry and artificial photosynthesis based on semiconductor materials with common photoinduced electronic excitations. The integration of the proposed research program with the Science, Technology and Research Scholars (STARS) program will naturally broaden the participation of underrepresented minorities in the physical sciences. Dissemination of research findings through the proposed Wiki interface will benefit the whole scientific community, facilitating the rapid exchange and distribution of results, software developments and pedagogical materials in the public domain.