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Complex-band structure: a method to determine the off-resonant electron transport in oligomers

Giorgos Fagas·Agapi Kambili·Marcus Elstner
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Abstract

We validate that off-resonant electron transport across {\it ultra-short} oligomer molecular junctions is characterised by a conductance which decays exponentially with length, and we discuss a method to determine the damping factor via the energy spectrum of a periodic structure as a function of complex wavevector. An exact mapping to the complex wavevector is demonstrated by first-principle-based calculations of: a) the conductance of molecular junctions of phenyl-ethynylene wires covalently bonded to graphitic ribbons as a function of the bridge length, and b) the complex-band structure of poly-phenyl-ethynylene.

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Giorgos Fagas, Agapi Kambili, Marcus Elstner. 2004-03-12. Complex-band structure: a method to determine the off-resonant electron transport in oligomers. https://doi.org/10.1016/j.cplett.2004.03.090

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