Phonon effects in molecular transistors

Quantal and classical treatment

A. Mitra, I. Aleiner, A. J. Millis

    Research output: Contribution to journalArticle

    Abstract

    We present a comprehensive theoretical treatment of the effect of electron-phonon interactions on molecular transistors, including both quantal and classical limits. We study both equilibrated and out of equilibrium phonons. We present detailed results for conductance, noise, and phonon distribution in two regimes. One involves temperatures large as compared to the rate of electronic transitions on and off the dot; in this limit our approach yields classical rate equations, which are solved numerically for a wide range of parameters. The other regime is that of low temperatures and weak electron-phonon coupling where a perturbative approximation in the Keldysh formulation can be applied. The interplay between the phonon-induced renormalization of the density of states on the quantum dot and the phonon-induced renormalization of the dot-lead coupling is found to be important. Whether or not the phonons are able to equilibrate in a time rapid compared to the transit time of an electron through the dot is found to affect the conductance. Observable signatures of phonon equilibration are presented. We also discuss the nature of the low-T to high-T crossover.

    Original languageEnglish (US)
    Article number245302
    JournalPhysical Review B - Condensed Matter and Materials Physics
    Volume69
    Issue number24
    DOIs
    StatePublished - Jun 2004

    Fingerprint

    Phonons
    Transistors
    phonons
    transistors
    Electron-phonon interactions
    Electrons
    transit time
    electron phonon interactions
    Semiconductor quantum dots
    crossovers
    electrons
    Lead
    quantum dots
    signatures
    formulations
    Temperature
    approximation
    electronics
    temperature

    ASJC Scopus subject areas

    • Condensed Matter Physics

    Cite this

    Phonon effects in molecular transistors : Quantal and classical treatment. / Mitra, A.; Aleiner, I.; Millis, A. J.

    In: Physical Review B - Condensed Matter and Materials Physics, Vol. 69, No. 24, 245302, 06.2004.

    Research output: Contribution to journalArticle

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