NICOP - Probing nonlocal thermal conduction in one-dimensional materials
Abstract
Fourier~s law of heat conduction is a local effect, i.e. heat transfer phenomena are solely determined by nearby temperatures rather than those far away. Deviations from the Fourier~s law, including ballistic thermal conduction and nonlocal thermal conduction, are predicted to occur when the sample size is smaller than the phonon mean free path. However, so far the experimental evidence for the nonlocal thermal conduction remains elusive. We have recently discovered macroscopic (from micrometers to millimeters) ballistic thermal conduction in SiGe nanowires and in carbon nanotubes. Thus, unlike previous works, the one~dimensional systems will make rigorous experimental investigations of the nonlocal thermal conduction possible. In this two~year proposal, we plan to employ three~terminal microscale platforms, combining with a laser~heating technique, to measure thermal transport properties of SiGe nanowires and carbon nanotubes at room temperature and low temperatures. Our investigation shall provide solid experimental proof of the nonlocal thermal conduction. SiGe is an important alloy that has been widely used in semiconductor electronics and carbon nanotubes are unique one~dimensional materials for nanodevices. How does heat flow in these materials? Could the heat propagate in a way that nobody has envisioned before? These are certainly fundamental questions eagerly waiting to be answered. The implementation of the project will also stimulate novel ideas in storing heat energy, controlling heat flows, or enabling portable thermoelectric power generators/refrigerators.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 03, 2017
- Source ID
- N629091712042
Entities
People
- Chih-Wei Chang
Organizations
- National Taiwan University
- Office of Naval Research
- United States Navy