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High On/Off Conductance Switching Ratio via H-Tautomerization in Quinone
Sherif Abdulkader Tawfik1, X Y Cui1, S P Ringer1
1School of Physics, ‡Australian Centre for Microscopy and Microanalysis, and School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney , Sydney, New South Wales 2006, Australia.
Abstract:
Through first-principles electron transport simulations using the nonequilibrium Green's function formalism together with density functional theory, we show that, upon H-tautomerization, a simple derivative of quinone can act as a molecular switch with high ON/OFF ratio, up to 70 at low bias voltage. This switching behavior is explained by the quantum interference effect, where the positional change of hydrogen atoms causes the energies of the transmission channels to overlap. Our results suggest that this molecule could have potential applications as an effective switching device.
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