Nanotechnology: better measurements of single molecule circuits

New work through Josh Hihath's organization at the UC Davis department of electrical and pc Engineering, published Feb. sixteen in the magazine Nature substances, ought to assist technologists make that jump. Hihath's laboratory has evolved a method to degree the conformation of single molecule "wiring," resolving a clash among theoretical predictions and experiments.

"we are looking to make transistors and diodes out of single molecules, and lamentably you can't currently control precisely how the molecule contacts the electrode or what the precise configuration is," Hihath said. "This new approach offers us a better dimension of the configuration, a good way to provide crucial statistics for theoretical modeling."

till now, there was a extensive hole among the predicted electrical behavior of single molecules and experimental measurements, with results being off via as lots as ten-fold, Hihath said.

Hihath's test uses a layer of alkanes (quick chains of carbon atoms, such as hexane, octane or decane) with either sulfur or nitrogen atoms on each end that permit them to bind to a gold substrate that acts as one electrode. The researchers then carry the gold tip of a Scanning Tunneling Microscope toward the floor to form a connection with the molecules. because the tip is then pulled away, the relationship will ultimately consist of a unmarried-molecule junction that incorporates six to 10 carbon atoms (depending on the molecule studied on the time).

through vibrating the top of the STM at the same time as measuring electrical current across the junction, Hihath and associates had been able to extract facts approximately the configuration of the molecules.

"This technique offers us records about each the electric and mechanical properties of the machine and tells us what the maximum possibly configuration is, some thing that became now not feasible earlier than," Hihath said.

The researchers hope the approach can be used to make higher predictions of ways molecule-scale circuits behave and layout better experiments.