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Updated: Nov 19, 2025

Characterization of Thermal Transport in One-dimensional Solid Materials
Published on: January 26, 2014
Thermal and electrical transport at nanosized metallic contacts: In the diffusive-ballistic region at room
Jianli Wang1, Lu Chen1, Cong Wang1
1School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro/Nano Biomedical Instruments, Southeast University, Nanjing 210096, China.
Abstract:
The Wiedemann-Franz law has been proved at the quantized metallic contacts but has never been verified at the nanosized contacts when the electrons travel in the diffusive-ballistic region. Herein, by developing a home-made inelastic tunneling spectroscope, the electrical and thermal resistances of the nanosized metallic contacts are investigated. The contact is established by pressing two wires crosswise against each other under the Lorentz force in the magnetic field. The nonmetallic surface layer is in situ removed by the resistive heating under high vacuum. The temperature dependence of the electrical contact resistance is used to separate the contributions from the diffusive and the ballistic transports. The thermal contact resistance is found to increase linearly with the electrical counterpart, indicating the validity of the Wiedemann-Franz law at the clean metallic contacts.
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