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arXiv · 0710.0916

Acoustic phonon transport through a double-bend quantum waveguide

Yi Ming·Zhexian Wang·Zejun Ding
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Abstract

In this work, using the scattering matrix method, we have investigated the transmission coefficients and the thermal conductivity in a double-bend waveguide structure. The transmission coefficients show strong resonances due to the scattering in the midsection of a double-bend structure; the positions and the widths of the resonance peaks are determined by the dimensions of the midsection of the structure. And the scattering in the double-bend structure makes the thermal conductivity decreases with the increasing of the temperature first, then increases after reaches a minimum. Furthermore, the investigations of the multiple double-bend structures indicate that the first additional double-bend structure suppresses the transmission coefficient and the frequency gap formed; and the additional double-bend structures determine the numbers of the resonance peaks at the frequency just above the gap region. These results could be useful for the design of phonon devices.

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Yi Ming, Zhexian Wang, Zejun Ding. 2007-10-04. Acoustic phonon transport through a double-bend quantum waveguide. https://doi.org/10.1016/j.physleta.2005.10.047

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