Thermal conductance quantum

In physics, the thermal conductance quantum g_0 describes the rate at which heat is transported through a single ballistic phonon channel. It is given by:

g_{0} = \frac{\pi^2 {k_B}^2 T}{3h} \approx (9.456\times10^{-13} W/K^{2})T.

The thermal conductance of any electrically insulating structure that exhibits ballistic phonon transport is a positive integer multiple of g_0. The thermal conductance quantum was first measured in 2000.[1] These measurements employed suspended silicon nitride nanostructures that exhibited a constant thermal conductance of 16g_0 at temperatures below approximately 0.6 kelvin.

For ballistic electrical conductors, the electron contribution to the thermal conductance is also quantized as a result of the electrical conductance quantum and the Wiedemann–Franz law.

References

  1. ↑ Schwab, K.; E. A. Henriksen; J. M. Worlock; M. L. Roukes (2000). "Measurement of the quantum of thermal conductance". Nature 404 (6781): 974–7. doi:10.1038/35010065. PMID 10801121.

See also

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