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Enlargement of the silicon nitride membrane. The colors represent the measured motion of the membrane in the out of plane direction. Red means that part of the membrane moves upward, and blue means that part moves downwards. Credit: Albert Schliesser and Xiang Xi When a drummer hits a drum, the surface vibrates and creates sound—a signal we recognize as music. But once those vibrations stop, the signal disappears. Now imagine a drumhead that’s incredibly thin, only about 10 millimeters wide, and covered in tiny triangular holes. Scientists have created exactly that, and it does something extraordinary. Researchers at the Niels...

The study is the first ever to prove that acoustic phonons (particles responsible for the transmission of both sound and heat) contain magnetic properties, The Ohio State University reported. The team of researchers demonstrated that a magnetic field about the size of an MRI was able to reduce the amount of heating flowing through a semiconductor by about 12 percent. "This adds a new dimension to our understanding of acoustic waves," said Joseph Heremans, Ohio Eminent Scholar in Nanotechnology and professor of mechanical engineering at Ohio State. "We've shown that we can steer heat magnetically. With a strong enough magnetic...

Carbon nanotubes are wrapped in TNA © Nature Materials A fundamentally new type of power generation may be on the horizon thanks to researchers in the US and Korea who have created a nanotube 'fuse' that harnesses the energy from chemical reactions. The device converts chemical energy into electrical energy, yet is so small compared with traditional batteries that it opens the door to applications such as floating sensors or new fuel cells. Carbon nanotubes are known to have unusually high thermal conductivity because of a streamlined way in which packets of heat energy, known as phonons, can travel through...