Friday, October 16, 2009

This week in nanotechnology, October 9-16, 2009

In an effort to make graphene more useful in electronics applications, Kansas State University engineers made a golden discovery – gold "snowflakes" on graphene. Functionalizing graphene with gold allows controlling its electronics properties.

Other graphene-related findings – previously considered possible by physicists but only now being seen in the laboratory – show that electrons in graphene can interact strongly with each other. The behavior is similar to superconductivity observed in some metals and complex materials, marked by the flow of electric current with no resistance and other unusual but potentially useful properties. In graphene, this behavior results in a new liquid-like phase of matter consisting of fractionally charged quasi-particles, in which charge is transported with no dissipation.

Diodes are critical components for a broad array of applications, from power conversion equipment, to radios, logic gates, photodetectors and light-emitting devices. In each case, diodes are components that allow current to flow in one direction around an electrical circuit but not the other. Researchers have now managed for a molecule to perform this feat – thereby creating a single-molecule diode.

Searching for biomarkers that can warn of diseases such as cancer while they are still in their earliest stage is likely to become far easier thanks to an innovative biosensor chip developed by Stanford University researchers. The sensor, which uses magnetic detection nanotechnology they had developed previously, can detect a given cancer-associated protein biomarker at a concentration as low as one part out of a hundred billion (or 30 molecules in a cubic millimeter of blood).

A team of scientists in Germany have succeeded in applying a novel optical method to nanomechanical oscillators. On-chip glass cylinders with diameters around 50 microns which are capable of storing light played a key role in the study. The scientists could show that the optical near-field, that is the light-field that is leaking out of the glass cylinders, can be used as actuator and sensitive probe for nanomechanical oscillators.

A team of chemists at the University of Rochester have begun work on a new kind of system to use artificial photosynthesis and carbon nanotubes to generate hydrogen fuel with sunlight.

Spider silk is a fascinating biopolymer that is stronger than steel and more elastic than rubber. Most of the world's 40,000 species of spiders produce a silken thread that possesses a unique combination of mechanical properties: strength (its tensile strength is about five times as strong a steel of the same density), extensibility (up to 30%) and toughness (its ability to absorb a large amount of energy without breaking). Researchers are working on fabricating high-performance artificial muscles from spider silk.