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arXiv · 1012.3856

Interaction-induced negative differential resistance in asymmetric molecular junctions

Martin Leijnse·Wei Sun·Mogens Brøndsted Nielsen·Per Hedegård·Karsten Flensberg
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Abstract

Combining insights from quantum chemistry calculations with master equations, we discuss a mechanism for negative differential resistance (NDR) in molecular junctions, operated in the regime of weak tunnel coupling. The NDR originates from an interplay of orbital spatial asymmetry and strong electron-electron interaction, which causes the molecule to become trapped in a non-conducting state above a voltage threshold. We show how the desired asymmetry can be selectively introduced in individual orbitals in e.g., OPE-type molecules by functionalization with a suitable side group, which is in linear conjugation to one end of the molecule and cross-conjugated to the other end.

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Martin Leijnse, Wei Sun, Mogens Brøndsted Nielsen, Per Hedegård, Karsten Flensberg. 2010-12-17. Interaction-induced negative differential resistance in asymmetric molecular junctions. https://doi.org/10.1063/1.3560474

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