Materials World Network: Collaborative Research: Decoherence, Correlations and Spin Effects in Nanostructured Materials

Oakland University, Rochester MI

Investigators

Abstract

This Materials World Network/Inter-American Materials Collaboration award supports a joint research and education program between participants in the US, Brazil, and Chile to explore effects of electron correlations in nanoscale or reduced-dimensionality materials: magnetic adatoms and molecules on surfaces, carbon nanotubes and graphene, and quantum dots in semiconductors and other materials. The increasing ability of experiments to probe correlations at the nanometer scale via advances in fabrication methods and local measurement techniques has given rise to a host of new questions about systems long considered understood in the bulk or in ensembles. Correlations between spins, competition between ordering and screening of magnetic impurities, possible quantum phase transitions between different regimes, and effects of decoherence, are all now explorable in experiments. The research is directed to address these issues, which are intrinsically important to basic physics understanding, as well as to possible technological uses in areas ranging from nanomagnetism and information storage to a host of new carbon-based electronic devices, and even quantum information processing by control of the spin degrees of freedom in electronic systems. The goal is to provide physical insights into correlated electron behaviors and to guide experiments to measure novel properties. Theoretical research is conducted in the US at Ohio University, the University of Florida, and Oakland University; in Brazil at the Pontificia Universidade Catolica do Rio de Janeiro and the Universidade Federal Fluminense; and in Chile at the Universidad Catolica del Norte, the Universidad Tecnica Federico Santa Maria, the Pontificia Universidad Catolica de Chile, and the Universidad de Antofagasta. Groups at these institutions combine their complementary expertise with different theoretical techniques, including the numerical renormalization group and the embedded cluster approximation, that are proven and reliable in treating nontrivial correlated problems. Close communication with experimental groups both inside the collaboration (at the Universidade Federal de Minas Gerais, Brazil) and outside maintain connections with real systems of interest. The project places significant emphasis on training young scientists in the US and Latin America, by engaging them in current research in a highly collaborative and international environment. Students and a postdoctoral fellow learn modern techniques that will provide them with tools for successful careers in science and with skills that will make them highly employable in industry. Junior researchers are brought together with leading experts at two mini-workshops, one held in Brazil, the other in the US. There are also concerted and well-planned efforts to reach a broader audience at the K-12 levels, through a web site with accessible articles on modern nanoscience developments, a program of school visits, and educational videos and attractive images showing research results. This award is co-funded with the Office of International Science and Engineering.