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

Abstract

Tunneling spectroscopy measurements have been carried out on a single molecule device formed by two Pd nanocrystals (dia. similar to 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) oil a background M-I-M characteristics. The NDR, feature occurs at similar to 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 (+/-similar to 0.3 V).