In the ballistic regime of transport, we derive the thermal resistance of metal nanowires connected to two heat baths. We find that the thermal resistances for any metal nanowire remain in a narrow and temperature-dependent interval between 0.447/$T$ and 14/$T$ ${\mathrm{m}}^2$ K/W. For cross-section edges larger than 20 nm, the thermal resistance can actually be estimated from $\frac{R_0}{(3\pi n_V^2){}^3}$, where $R_0$ is the quantum of resistance and $n_V$ refers to the electron density. This prediction yields a contact resistance one order of magnitude larger than the one of previous estimations. Significant consequences for application fields such as nanoelectronics, where nanowire sizes involve ballistic transport, are expected.

• Received 28 June 2010

DOI:https://doi.org/10.1103/PhysRevB.83.115425