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As a scientist, I always find it interesting to see how new research is covered in the media. I know how hard it is to write exciting stories about nanotechnology — and I also know how important it is to get good science out in the public imagination. But maybe it’s worth dissecting a story to see why some people think “nano” is overhyped and how much history exists in this field.

So my next few posts will be on a relatively recent article in the journal Nature, published on June 2, 2005 by Prof. Robert A. Wolkow of the University of Alberta. “Field regulation of single-molecule conductivity by a charged surface atom” accompanied by a “news and views” interpretation by Prof. Mark Ratner of Northwestern University (my Ph.D. advisor).

Basically, the researchers placed lines of styrene molecules down on a clean silicon surface using a scanning tunneling microscope (STM) to help place the molecules and to image the surface afterwards. The process of depositing the molecules on the surface restricts them to a small ordered line and forms a “dangling bond” (i.e., a charge) at the end of the line. They then go on to argue that this dangling bond can be used to switch the molecules nearby into a more highly conductive state — essentially arguing that the molecules function as molecular wires and the combination of the dangling bond and molecules form a set of molecular transistors.

There are several really nice bits in this work:

• Unlike earlier articles on single-molecule electronic devices, this shows a clear geometry of everything involved. Many previous articles have shown functioning single-molecule electronics but have not been able to image the device itself.
• The charge on the dangling bond is a well-defined quantity (i.e., one electron). This research illustrates that the electric field generated by a single electron is enough to cause significant electronic changes on the molecular scale.
• Since the device is formed on a silicon surface, it’s slightly more clear how to make a “molecular electronics chip” integrating into current silicon devices. Previous works often used metal-molecule-metal wires, which would be difficult to make on a large scale.

In the next few posts, I’m going to consider how this article was covered in various press articles and the University of Alberta press release. Some coverage is a bit more sensational than others…