Limits to thermal transport in nanoscale metal bilayers due to weak electron-phonon coupling in Au and Cu

Wei Wang, David G. Cahill

Research output: Contribution to journalArticle


Weak electron-phonon coupling in Au and Cu produces a significant thermal resistance when heat flows from a thin Pt layer into a thin Au or Cu layer on picosecond time scales. Metal bilayers (Pt/Au and Pt/Cu) were prepared by magnetron sputter deposition; thermal transport in the bilayers was studied by time domain thermoreflectance in the temperature range 38<T<300K. Analysis of heat transfer in the bilayer yields the electron-phonon coupling parameter g(T) of Au and Cu. Our results for g(T) are consistent with the temperature dependence predicted by the two-temperature model of Kaganov et al. and help bridge the gap between data obtained using pump-probe spectroscopy at room temperature and electrical measurements at low temperatures.

Original languageEnglish (US)
Article number175503
JournalPhysical review letters
Issue number17
StatePublished - Oct 26 2012


ASJC Scopus subject areas

  • Physics and Astronomy(all)

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