Boundary resistance breakthrough

Under our new AFOSR grant, Jaeho, Elah, and Zijian are sorting out the electron and phonon contributions for the first time using nanolayers of metals, semi-metals, and dielectrics.

With AFOSR support, Zijian Li, Jaeho Lee, and Elah Bozorg Grayeli, are sorting out the electron and phonon contributions to thermal boundary resistance.  Thermal boundary resistance is a long-standing problem in the heat transfer community, and one of the major remaining challenges is to understand metallic and semi-metallic systems in which both electrons and phonons contribution to conduction. 

In these papers, Jaeho, Elah, and Zijian are using ultrafast optical characterization and patterned bridges down to 50 nm to measure volume and interface resistances in nanolayer samples.  Transport analysis and experimental substraction methodologies are used to isolate the interface resistances, and then additional measurements serve to separate the electron and phonon contributions.