When graduate student Pengpeng Zhang successfully imaged a piece of silicon just 10 nanometers-or a millionth of a centimeter-in thickness, she and her University of Wisconsin-Madison co-researchers were puzzled. According to established thinking, the feat should be impossible because her microscopy method required samples that conduct electricity.
"After she did it, we realized, Hey, this silicon layer is really thin-its much thinner than what people normally use," says UW-Madison physicist Mark Eriksson. "In fact, its thin enough that it should be very hard to run a current through it. So we began asking, Why is this working?"
A team led by College of Engineering professors Paul Evans, Irena Knezevic and Max Lagally and physics professor Eriksson has now answered that question. Writing in the Feb. 9 issue of the journal Nature, they have shown that when the surface of nanoscale silicon is specially cleaned, the surface itself facilitates current flow in thin layers that ordinarily wont conduct. In fact, conductivity at the nanoscale is completely independent of the added impurities, or dopants, that usually control silicons electrical properties, the team reports.
Paul Evans | EurekAlert!
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Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
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Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
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In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
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