Electron and phonon transport in silicon nanowires: Atomistic approach to thermoelectric properties

    Research output: Contribution to journalJournal articleResearchpeer-review

    470 Downloads (Pure)


    We compute both electron and phonon transmissions in thin disordered silicon nanowires (SiNWs). Our atomistic approach is based on tight-binding and empirical potential descriptions of the electronic and phononic systems, respectively. Surface disorder is modeled by introducing surface silicon vacancies. It is shown that the average phonon and electron transmissions through long SiNWs containing many vacancies can be accurately estimated from the scattering properties of the isolated vacancies using a recently proposed averaging method [Markussen et al., Phys. Rev. Lett. 99, 076803 (2007)]. We apply this averaging method to surface disordered SiNWs in the diameter range of 1–3 nm to compute the thermoelectric figure of merit ZT. It is found that the phonon transmission is affected more by the vacancies than the electronic transmission leading to an increased thermoelectric performance of disordered wires, in qualitative agreement with recent experiments. The largest ZT>3 is found in strongly disordered 111-oriented wires with a diameter of 2 nm.
    Original languageEnglish
    JournalPhysical Review B Condensed Matter
    Issue number3
    Pages (from-to)035415
    Publication statusPublished - 2009

    Bibliographical note

    Copyright 2009 American Physical Society


    • tight-binding calculations
    • elemental semiconductors
    • surface phonons
    • thermoelectricity
    • silicon
    • vacancies (crystal)
    • surface states


    Dive into the research topics of 'Electron and phonon transport in silicon nanowires: Atomistic approach to thermoelectric properties'. Together they form a unique fingerprint.

    Cite this