Observation of second sound in graphite over 200 K
Author(s)
Ding, Zhiwei
Chen, Ke
Song, Bai
Shin, Jungwoo
Maznev, Alexei A.
Nelson, Keith A.
Chen, Gang
Date Issued
January 12, 2022
Journal
Nature Communications
Publisher
Springer Science and Business Media LLC
Citation
Ding, Zhiwei, Chen, Ke, Song, Bai, Shin, Jungwoo, Maznev, Alexei A. et al. 2022. "Observation of second sound in graphite over 200 K." Nature Communications, 13 (1).
Version
Final published version
Abstract
Abstract
Second sound refers to the phenomenon of heat propagation as temperature waves in the phonon hydrodynamic transport regime. We directly observe second sound in graphite at temperatures of over 200 K using a sub-picosecond transient grating technique. The experimentally determined dispersion relation of the thermal-wave velocity increases with decreasing grating period, consistent with first-principles-based solution of the Peierls-Boltzmann transport equation. Through simulation, we reveal this increase as a result of thermal zero sound—the thermal waves due to ballistic phonons. Our experimental findings are well explained with the interplay among three groups of phonons: ballistic, diffusive, and hydrodynamic phonons. Our ab initio calculations further predict a large isotope effect on the properties of thermal waves and the existence of second sound at room temperature in isotopically pure graphite.
MIT Department
Massachusetts Institute of Technology. Research Laboratory of Electronics
Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
Lincoln Laboratory
Massachusetts Institute of Technology. Department of Physics
Terms of Use
Creative Commons Attribution 4.0 International license
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1038/s41467-021-27907-z
