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A single molecule switch based on two Pd nanocrystals linked by a conjugated dithiol

Ved Varun Agrawal·Reji Thomas·G. U. Kulkarni·C. N. R. Rao
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Abstract

Tunneling spectroscopy measurements have been carried out on a single molecule device formed by two Pd nanocrystals (dia, $\sim$5 nm) electronically coupled by a conducting molecule, dimercaptodiphenylacetylene. The I-V data, obtained by positioning the tip over a nanocrystal electrode, exhibit negative differential resistance (NDR) on a background M-I-M characteristics. The NDR feature occurs at $\sim$0.67 V at 300 K and shifts to a higher bias of 1.93 V at 90 K. When the tip is held in the middle region of the device, a coulomb blockade region is observed ($\pm\sim$0.3 V).

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Ved Varun Agrawal, Reji Thomas, G. U. Kulkarni, C. N. R. Rao. 2005-07-06. A single molecule switch based on two Pd nanocrystals linked by a conjugated dithiol. https://arxiv.org/abs/cond-mat/0507147

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