Friday, May 6, 2011

This week in nanotechnology - May 6, 2011

With the creation of a 3-D nanocone-based solar cell platform, a team led by Oak Ridge National Laboratory's Jun Xu has boosted the light-to-power conversion efficiency of photovoltaics by nearly 80 percent. The technology substantially overcomes the problem of poor transport of charges generated by solar photons. These charges – negative electrons and positive holes – typically become trapped by defects in bulk materials and their interfaces and degrade performance.

A data memory can hardly be any smaller: researchers have stored quantum information in a single atom. The researchers wrote the quantum state of single photons, i.e. particles of light, into a rubidium atom and read it out again after a certain storage time. This technique can be used in principle to design powerful quantum computers and to network them with each other across large distances.

MIT chemical engineers have designed a new type of drug-delivery nanoparticle that exploits a trait shared by almost all tumors: They are more acidic than healthy tissues. Such particles could target nearly any type of tumor, and can be designed to carry virtually any type of drug. Like most other drug-delivering nanoparticles, the new MIT particles are cloaked in a polymer layer that protects them from being degraded by the bloodstream. However, the team designed this outer layer to fall off after entering the slightly more acidic environment near a tumor.
cloaked nanoparticle
The outer layer of this nanoparticle (in yellow) falls off in an acidic environment.

An international team of plasmonics researchers has developed a novel type of nanoantennas that could one day lead to advances in security applications for the detection of drugs and explosives. Nanoantennas work in much the same way as regular antennas, except they collect light instead of radio waves and are millions of times smaller.

New research paves way for the nanoscale self-assembly of organic building blocks, a promising new route towards the next generation of ultra-small electronic devices. Ring-like molecules with unusual five-fold symmetry bind strongly to a copper surface, due to a substantial transfer of charge, but experience remarkably little difficulty in sideways diffusion, and exhibit surprisingly little interaction between neighbouring molecules. This unprecedented combination of features is ideal for the spontaneous creation of high-density stable thin films, comprising a pavement of these organic pentagonal tiles, with potential applications in computing, solar power and novel display technologies.