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Current collapse in tunneling transport through benzene

M. H. Hettler·W. Wenzel·M. R. Wegewijs·H. Schoeller
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Abstract

We investigate the electrical transport through a system of benzene coupled to metal electrodes by electron tunneling. Using electronic structure calculations, a semi--quantitative model for the pi-electrons of the benzene is derived that includes general two-body interactions. After exact diagonalization of the benzene model the transport is computed using perturbation theory for weak electrode-benzene coupling (golden rule approximation). We include the effect of an applied electric field on the molecular states, as well as radiative relaxation. We predict a current collapse and strong negative differential conductance due to a ``blocking'' state when the electrode is coupled to the para-position of benzene. In contrast, for coupling to the meta-position, a series of steps in the I-V curve is found.

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M. H. Hettler, W. Wenzel, M. R. Wegewijs, H. Schoeller. 2002-07-19. Current collapse in tunneling transport through benzene. https://doi.org/10.1103/physrevlett.90.076805

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