Description

The quantitative understanding of 2D atomic layer interface thermal resistance based on Raman characterization is significantly hindered by unknown sample-to-sample optical properties variation, interface-induced optical interference, off-normal laser irradiation, and large thermal-Raman calibration uncertainties. In this work, we develop a novel energy transport state resolved Raman (ET-Raman) to resolve these critical issues, and also consider the hot carrier diffusion, which is crucial but has been rarely considered during interface energy transport study. In ET-Raman, by constructing two steady heat conduction states with different laser spot sizes, we differentiate the effect of R and hot carrier diffusion coefficient. By constructing an extreme state of zero/negligible heat conduction using a picosecond laser, we differentiate the effect of R and material’s specific heat. In the end, we precisely determine interface thermal resistance and hot carrier diffusion coefficient without the need of laser absorption and temperature rise of the 2D atomic layer. To our best knowledge, ET-Raman could also be used for carrier transport and interface energy coupling study of other 2D materials in the most applicable forms with high accuracy and confidence. Such an impactful state-resolved technique opens up a new way for efficient and accurate 2D materials thermal and electrical properties characterization.

Contributing Authors

  • Pengyu Yuan
    Lawrence Berkeley National Laboratory
  • Xinwei Wang
    Iowa State University
Pengyu Yuan
Lawrence Berkeley National Laboratory
Track: Laser Nanomanufacturing
Session: Nanomaterial Characterization
Day of Week: Monday
Date/Time:
Location:

Keywords

  • Interface Thermal Transport
  • Picosecond Laser Heating
  • Raman Spectroscopy
  • Thermal Conductivity
  • Thickness Dependence