title: Nanostructures Significantly Enhance Thermal Transport across Solid Interfaces.
abstract: The efficiency of thermal transport across solid interfaces presents large challenges for modern technologies such as thermal management of electronics. In this paper, we report the first demonstration of significant enhancement of thermal transport across solid interfaces by introducing interfacial nanostructures. Analogous to fins that have been used for macroscopic heat transfer enhancement in heat exchangers, the nanopillar arrays patterned at the interface help interfacial thermal transport by the enlarged effective contact area. Such a benefit depends on the geometry of nanopillar arrays (e.g., pillar height and spacing), and a thermal boundary conductance enhancement by as much as ∼88% has been measured using the time-domain thermoreflectance technique. Theoretical analysis combined with low-temperature experiments further indicates that phonons with low frequency are less influenced by the interfacial nanostructures due to their large transmissivity, but the benefit of the nanostructure is fully developed at room temperature where higher frequency phonons dominate interfacial thermal transport. The findings from this work can potentially be generalized to benefit real applications such as the thermal management of electronics.
authors.affiliation: Department of Aerospace and Mechanical Engineering and ‡Center for Sustainable Energy at Notre Dame, University of Notre Dame , Notre Dame, Indiana 46556, United States.
authors.forename: Eungkyu
authors.identifier: http://orcid.org/0000-0002-0211-0727
authors.initials: E
authors.lastname: Lee
authors.affiliation: Department of Aerospace and Mechanical Engineering and ‡Center for Sustainable Energy at Notre Dame, University of Notre Dame , Notre Dame, Indiana 46556, United States.
authors.forename: Teng
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Department of Aerospace and Mechanical Engineering and ‡Center for Sustainable Energy at Notre Dame, University of Notre Dame , Notre Dame, Indiana 46556, United States.
authors.forename: Taehee
authors.initials: T
authors.lastname: Yoo
authors.affiliation: Department of Aerospace and Mechanical Engineering and ‡Center for Sustainable Energy at Notre Dame, University of Notre Dame , Notre Dame, Indiana 46556, United States.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Guo
authors.affiliation: Department of Aerospace and Mechanical Engineering and ‡Center for Sustainable Energy at Notre Dame, University of Notre Dame , Notre Dame, Indiana 46556, United States.
authors.forename: Tengfei
authors.identifier: http://orcid.org/0000-0003-3940-8786
authors.initials: T
authors.lastname: Luo
keywords: nanostructures; solid interfaces; thermal boundary conductance; thermal boundary resistance; thermal managements