This award supports theoretical research and education in condensed matter physics on the subject of transport in quasi-one-dimensional systems. Investigations will be undertaken into transport properties of ultra-thin wires, e.g. carbon nanotubes, semiconductor nanowires, polymer nanofibers, graphene ribbons. Research is motivated by the fact that such systems often show distinctly unconventional dependences on temperature, external fields, and other experimentally tunable parameters, as well as large sample-to-sample variability. A program of theoretical investigations is undertaken towards providing theoretical descriptions and computer simulations to provide understanding the physics behind such anomalies. The transport characteristics of primary importance are ensemble-averaged conductivity, its dependence on intrinsic and external parameters, its statistical distribution, and its temporal and spatial fluctuations (noise). The special focus of the proposed research is to elucidate the role of cooperative impurity effects and Coulomb interactions at the root of the observed transport laws. Additionally, some relatively new phenomena that arise from a combined action of multiple impurities in systems with a finite concentration of dopants and defects are addressed. The PI will investigate the degree to which these phenomena are pervasive in such one-dimensional and quasi-one-dimensional conductors. It is expected that the phenomena originate from the tight geometric constraints imposed on the current pathways by the reduced dimensionality and from strong electron-electron interactions typical of these systems.
This research is undertaken at an institution with an ethnically diverse student body, allowing the PI to develop components of the research program that can be conducted in a close collaboration with a team of talented and ethnically diverse graduate and undergraduate students. The research engagement allows students to gain technical knowledge and problem-solving skills. The undergraduate students particularly have opportunities to participate in cutting-edge research in an environment not otherwise available. Beyond this, the PI extends the impact of the program with outreach activities at summer science camps for area high school students.
NON-TECHNICAL SUMMARY: This award supports theoretical research and education in condensed matter physics on how electric charge moves through systems of ultra-thin wire-like materials that are part of the developments in nanotechnology. The scientific questions addressed in this proposal involve the peculiar and unusual properties that develop with extreme miniaturization of electronic components that are the core elements of nanotechnology. Particular examples of the extreme miniaturization include a number of structures that are long but very narrow and are termed nanowires. Nanowires may be constructed from a variety of materials such as metals, polymers or semiconductors. Independent of many specifics, there are universal characteristics of transport in nanowires that have amorphous structure, i.e. noncrystalline, at the molecular and atomic level. Understanding the origins of properties that are similar when the materials are extremely different is of keen interest for future technological applications being considered by a broad community of researcher in pure and applied sciences. Reliable answers to such questions that arise from unconventional properties of electrical and heat flow in nanostructures is fundamental to most future applications on nanotechnology.
This research is undertaken at an institution with an ethnically diverse student body, allowing the PI to develop components of the research program that can be conducted in a close collaboration with a team of talented and ethnically diverse graduate and undergraduate students. The research engagement allows students to gain technical knowledge and problem-solving skills. The undergraduate students particularly have opportunities to participate in cutting-edge research in an environment not otherwise available. Beyond this, the PI extends the impact of the program with outreach activities at summer science camps for area high school students.
