The controversy centres on two papers that appeared in the journals Nature and Science last year. Schön’s group reported that they had made a transistor from a single layer of molecules in an article that appeared in Nature on 18 October. The researchers then said they had made a transistor from a single molecule, a result that appeared in Science on 8 November. The final figures in each paper – which showed the voltage characteristics of the devices – look very similar.

The confusion was compounded when a professor of physics at Cornell University, Paul McEuen, noticed that a similar graph had also appeared in an article by Schön’s team that was published in Science on 11 February 2000. This time, the scale of the graph was a factor of five larger. A second graph in this article is also similar – except for a factor of two – to a graph in an article by Schön’s group that appeared in Science on 28 April 2000.

There are further doubts about graphs published subsequently in the journals Applied Physics Letters and Synthetic Metals.

Bell Labs spokesman Saswato Das told the New York Times that the independent scientists appointed for the investigation would be granted full access. “There are serious scientific concerns, and we would like them reviewed fully, independently and objectively,” he said. Malcolm Beasley of Stanford University in the US is chairing the external review panel.

Beyond an assertion that he will do everything he can to help the inquiry, Schön is declining to comment until it is completed. His team at Bell Labs has published dozens of papers since the beginning of 2000, many of them in Nature and Science.