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Mesoscopic Phonon Transmission through a Nanowire-Bulk Contact

Chun-Min Chang·Michael R. Geller
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Abstract

We calculate the frequency-dependent mesoscopic acoustic phonon transmission probability through the abrupt junction between a semi-infinite, one-dimensional cylindrical quantum wire and a three-dimensional bulk insulator, using a perturbative technique that is valid at low frequency. The system is described using elasticity theory, and traction-free boundary conditions are applied to all free surfaces. In the low-frequency limit the transmission probability vanishes as the frequency squared, the transport being dominated by the longitudinal channel, which produces a monopole source of elastic radiation at the surface of the bulk solid. The thermal conductance between an equilibrated wire nonadiabatically coupled to a bulk insulator should therefore vanish with temperature at temperature cubed.

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Chun-Min Chang, Michael R. Geller. 2004-09-24. Mesoscopic Phonon Transmission through a Nanowire-Bulk Contact. https://doi.org/10.1103/physrevb.71.125304

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