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arXiv · 1801.10379

Transmission eigenchannels for coherent phonon transport

J. C. Klöckner·J. C. Cuevas·F. Pauly
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Abstract

We present a procedure to determine transmission eigenchannels for coherent phonon transport in nanoscale devices using the framework of nonequilibrium Green's functions. We illustrate our procedure by analyzing a one-dimensional chain, where all steps can be carried out analytically. More importantly, we show how the procedure can be combined with ab initio calculations to provide a better understanding of phonon heat transport in realistic atomic-scale junctions. In particular, we study the phonon eigenchannels in a gold metallic atomic-size contact and different single-molecule junctions based on molecules such as an alkane chain, C$_{60}$, and a brominated benzene-diamine, where in this latter case destructive phonon interference effects take place.

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J. C. Klöckner, J. C. Cuevas, F. Pauly. 2018-01-31. Transmission eigenchannels for coherent phonon transport. https://doi.org/10.1103/physrevb.97.155432

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