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The Role of Quantum Interference in Determining Transport Properties of Organic Molecules

Kamil Walczak
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Abstract

An analytic approach to the electron transport phenomena in molecular devices is presented. Analyzed devices are composed of organic molecules attached to the two semi-infinite electrodes. Molecular system is described within the tight-binding model, while the coupling to the electrodes is analyzed through the use of Newns-Anderson chemisorption theory. The current-voltage (I-V) characteristics are calculated through the integration of transmission function in the standard Landauer formulation. The essential question of quantum interference effect of electron waves is discussed in three aspects: (i) the geometry of molecular bridge and (ii) the presence of an external magnetic field and (iii) the strength of the molecule-to-electrodes coupling.

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Kamil Walczak. 2004-02-26. The Role of Quantum Interference in Determining Transport Properties of Organic Molecules. https://arxiv.org/abs/cond-mat/0209169

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