Synchronised nanoscale oscillators may spur new devices
Synchronisation phenomena are everywhere in the physical world -- from circadian rhythms to side-by-side pendulum clocks coupled mechanically through vibrations in the wall. Researchers have now demonstrated synchronisation at the nanoscale, using only light, not mechanics. Two tiny mechanical oscillators, suspended just nanometers apart, can talk to each other and synchronise by means of nothing but light, according to new research published Dec. 5 in Physical Review Letters. Read more
Single-molecule 'electric car' taken for test drive
Scientists have shown off what can be described as the world's smallest electric car - made of a single, carefully designed molecule. The molecule has four branches that act as wheels, rotating when a tiny metal tip applied a small current to them. Read more
Caltech Researchers Design a New Nanomesh Material
Computers, light bulbs, and even people generate heat-energy that ends up being wasted. Thermoelectric devices, which convert heat to electricity and vice versa, harness that energy. But they're not efficient enough for widespread commercial use or are made from expensive or environmentally harmful rare materials. Now, Caltech researchers have developed a new type of material - a nanomesh, composed of a thin film with a grid-like arrangement of tiny holes - that could lead to efficient thermoelectric devices. Read more
Carbon nanotubes, the poster child of the burgeoning nanotechnology industry, could trigger diseases similar to those caused by asbestos, a study suggests.
A new type of carbon fibre, developed at the University of Cambridge, could be woven into super-strong body armour for the military and law enforcement. The researchers say their material is already several times stronger, tougher and stiffer than fibres currently used to make protective armour. The lightweight fibre, made up of millions of tiny carbon nanotubes, is starting to reveal exciting properties. Carbon nanotubes are hollow cylinders of carbon just one atom thick.
We've seen nanotechnology used to improve on traditional batteries before, but NASA now seems to be taking a slightly different tact, developing an actual "nanobattery" to provide power to other nanoscale devices. According to a recent patent application, its idea is to make use of the iron-containing protein ferritin, which apparently has the innate ability to carry either a positive or negative charge. In practice, one layer of ferritin would simply be stacked with another layer carrying the opposite charge, effectively forming a battery just a few nanometers thick. The capacity could then be further increased by adding more layers of ferritin, with the battery still remaining "stable and robust."
Astronauts can only endure space for about six months without irreversibly damaging their muscles, despite daily exercise. Unfortunately, it will take at least 30 months of space travel to reach Mars, making a manned flight unfeasible today. The National Aeronautics and Space Administration (NASA) recently reported progress toward a neural implant technology using carbon nanotubes that could enable space flights of indefinite periods. Read more
The ability of carbon nanotubes to withstand repeated stress yet retain their structural and mechanical integrity is similar to the behaviour of soft tissue, according to a new study from Rensselaer Polytechnic Institute. When paired with the strong electrical conductivity of carbon nanotubes, this ability to endure wear and tear, or fatigue, suggests the materials could be used to create structures that mimic artificial muscles or interesting electro-mechanical systems, researchers said.
Rice University chemists have discovered that tiny building blocks known as gold nanorods spontaneously assemble themselves into ring-like superstructures. This finding, which will be published as the inside cover article of the March 19 international edition of the chemistry journal Angewandte Chemie, could potentially lead to the development of novel nanodevices like highly sensitive optical sensors, superlenses, and even invisible objects for use in the military.
Researchers have created an anti-reflective coating that allows light to travel through it, but lets almost none bounce off its surface. At least 10 times more effective than the coating on sunglasses or computer monitors, the material, which is made of silica nanorods, may be used to channel light into solar cells or allow more photons to surge through the surface of a light-emitting diode (LED). Publishing in the March 1, 2007, Nature Photonics, lead author Jong Kyu Kim and a team from Rensselaer Polytechnic Institute in Troy, N.Y., reveal how they crafted the coating, which reflects almost as little light as do molecules of air. Guided by National Science Foundation-supported electrical engineer Fred Schubert, the researchers developed a process based on an already common method for depositing layers of silica, the building block of quartz, onto computer chips and other surfaces. The method grows ranks of nanoscale rods that lie at the same angle. That degree of the angle is determined by temperature. Under a microscope, the films look like tiny slices of shag carpet. By laying down multiple layers, each at a different angle, the researchers created thin films that are uniquely capable of controlling light. With the right layers in the right configuration, the researchers believe they can even create a film that will reflect no light at all. One critical application for the material is in the development of next-generation solar cells. By preventing reflections, the coating would allow more light, and more wavelengths of light, to transmit through the protective finish on a solar cell surface and into the cell itself. Engineers may be able to use such a technique to boost the amount of energy a cell can collect, bypassing current efficiency limits. Another application would involve coating LEDs to eliminate reflections that cut down the amount of light the LED can emit. The researchers hope the efficiency gains could allow the light sources to compete more effectively with fluorescent and incandescent bulbs. So, they will next focus their attention on solid state lighting.