Current rectification in a single molecule diode: the role of electrode coupling. (2nd July 2015)

• Record Type: Journal Article
• Authors: Sherif, Siya; Rubio-Bollinger, Gabino; Pinilla-Cienfuegos, Elena; Coronado, Eugenio; Cuevas, Juan Carlos; Agraït, Nicolás
• Is Part Of: Nanotechnology. Volume 26:Number 29(2015)
• Publication Date: 2015-07-02
• Subjects: single-molecule rectification -- molecular electronics -- polyoxometalate; 85.65.+h -- 87.64.Dz -- 85.30.Mn; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/0957-4484/26/29/291001
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: We demonstrate large rectification ratios ( ) in single-molecule junctions based on a metal-oxide cluster (polyoxometalate), using a scanning tunneling microscope (STM) both at ambient conditions and at low temperature. These rectification ratios are the largest ever observed in a single-molecule junction, and in addition these junctions sustain current densities larger than 10 5 A cm −2 . By following the variation of the I – V characteristics with tip–molecule separation we demonstrate unambiguously that rectification is due to asymmetric coupling to the electrodes of a molecule with an asymmetric level structure. This mechanism can be implemented in other type of molecular junctions using both organic and inorganic molecules and provides a simple strategy for the rational design of molecular diodes.