Temperature dependent conductances of deformable molecular devices

Balázs Dóra; András Halbritter

doi:10.1103/physrevb.80.155402

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arXiv · 0906.0935

Temperature dependent conductances of deformable molecular devices

Balázs Dóra·András Halbritter

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Abstract

Transport through a molecular device coupled to a vibrational mode is studied. By mapping it to the Yu-Anderson model in the large contact broadening limit, the zero bias electric and heat conductances are evaluated non-perturbatively. These exhibit a step from their T=0 value to half of its value as T increases due to the opening of the inelastic scattering channel. The spectral function exhibits the Franck-Condon suppressed multiphonon steps. The Wiedemann-Franz law is satisfied at low and high temperatures, but is violated in between. Relations to experiments are discussed.

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Balázs Dóra, András Halbritter. 2009-06-04. Temperature dependent conductances of deformable molecular devices. https://doi.org/10.1103/physrevb.80.155402

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