This CAREER project is aimed at tailoring phonon transport phenomena in nanostructures through the control of coherence and anharmonicity effects. Coherence-scale phenomena are prominent in, for example, field-effect transistors while anharmonicity affects transport at interfaces separating hard and soft matter. The long-term goal of this project is to enable and advance pertinent applications ranging from nanoelectronics to nanomedicine. Theoretical tools will be developed to analyze coherence effects, while novel experiments will be devised and conducted to probe the spectral properties of phonons participating in thermal transport at hard-soft interfaces.
Intellectual Merit: A systematic investigation of the role of anharmonicity (in soft matter) and coherence (in hard matter) during thermal transport will be conducted. A phonon wave transport theory will be extended to include particle-like behavior to enable the prediction of thermal responses in sub-10 nanometer transistors. A novel time-resolved Raman scattering approach to experimentally probe temperature-dependent anharmonic shifts in the frequencies of macromolecules will also be developed, providing a means to gain insight into the anharmonic dynamics of phonons in soft matter.
Broader Impacts: The project is aimed at developing a fundamental understanding of thermal transport in soft and hard matter, and across interfaces separating these materials. This understanding may lead to new pathways for developing small-scale transistors, discovering new cancer therapies, and creating novel energy harvesting thermoelectric materials. The education plan will motivate students at multiple levels to pursue careers and research in energy conversion and the thermal sciences. New laboratory experiences will be incorporated into undergraduate laboratory courses at the PI's institution. Likewise, a new graduate course in nanotransport will be developed. Teaching kits will be developed for K-12 teachers, and outreach will include summer camps to introduce energy conversion principles to high school girls.
