Visualizing Energy Transfer at Buried Interfaces in Layered Materials Using Picosecond X-Rays

Clara Nyby, Aditya Sood, Peter Zalden, Alexander J. Gabourie, Philipp Muscher, Daniel Rhodes, Ehren Mannebach, Jeff Corbett, Apurva Mehta, Eric Pop, Tony F. Heinz, Aaron M. Lindenberg

Research output: Contribution to journalArticlepeer-review

13 Scopus citations


Understanding the fundamentals of nanoscale heat propagation is crucial for next-generation electronics. For instance, weak van der Waals bonds of layered materials are known to limit their thermal boundary conductance (TBC), presenting a heat dissipation bottleneck. Here, a new nondestructive method is presented to probe heat transport in nanoscale crystalline materials using time-resolved X-ray measurements of photoinduced thermal strain. This technique directly monitors time-dependent temperature changes in the crystal and the subsequent relaxation across buried interfaces by measuring changes in the c-axis lattice spacing after optical excitation. Films of five different layered transition metal dichalcogenides MoX2 [X = S, Se, and Te] and WX2 [X = S and Se] as well as graphite and a W-doped alloy of MoTe2 are investigated. TBC values in the range 10–30 MW m−2 K−1 are found, on c-plane sapphire substrates at room temperature. In conjunction with molecular dynamics simulations, it is shown that the high thermal resistances are a consequence of weak interfacial van der Waals bonding and low phonon irradiance. This work paves the way for an improved understanding of thermal bottlenecks in emerging 3D heterogeneously integrated technologies.

Original languageEnglish (US)
Article number2002282
JournalAdvanced Functional Materials
Issue number34
StatePublished - Aug 1 2020
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • General Chemistry
  • General Materials Science
  • Electrochemistry
  • Biomaterials


  • heterogeneous integration
  • thermal boundary conductance
  • time-resolved X-ray diffraction
  • transition metal dichalcogenides


Dive into the research topics of 'Visualizing Energy Transfer at Buried Interfaces in Layered Materials Using Picosecond X-Rays'. Together they form a unique fingerprint.

Cite this