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Using lasers and metal powder, Australian scientists have created a super strong, super lightweight new “metamaterial” — but they got the idea for this sci fi-sounding creation from plants. The challenge: Materials that are strong yet lightweight, such as carbon fiber and graphene, are used to make everything from medical implants to airships, and developing ones with ever greater “strength-to-weight ratios” is the goal of many material scientists. In pursuit of that goal, some have turned to nature, looking for ways to replicate in metal the hollow lattice structures, like those in the Victoria water lily, that make some plants...

According to a new paper published today in Nature Materials, the newly engineered material creates a robust acoustic structure that can control in unusual ways the propagation and localization of sound even when fabrication imperfections exist. This unique property may improve technologies that use sound waves, such as sonars and ultrasound devices, making them more resistant to defects. Using topological principles, researchers predicted and later discovered topological insulators—special materials that conduct electric currents only on their edges, not in the bulk. Their unusual conduction properties stem from the topology of their electronic band gap, and they are therefore unusually resistant...

The gel can flow freely as a liquid until poure back into water, where it reforms its original shapeIt might look like a pink gloopy liquid to begin with but when you pour Dan Lou's DNA hydrogel into water it spontaneously reforms into its original shape. Even the Cornell researchers aren't exactly sure why their new material does what it does, but the potential applications are causing excitement.The hydrogels are made from incredibly long strands of DNA that tangle up, trapping water in its structure. The researchers think that once the hydrogels are taken out of water they collapse under...

Researchers in the US have used an artificially-structured "metamaterial" to build a device that can control highly-elusive terahertz (THz) radiation. The modulator is claimed to be ten-times better at switching a THz beam than previous designs and could pave the way for the use of the radiation in a wide range of applications in chemistry, astronomy and even airport security (Nature 444 597). Sandwiched between the microwave and infrared regions of the electromagnetic spectrum (at about 300 GHz to 10 THz), THz radiation is notoriously difficult to work with. It is too high frequency to be manipulated electrically like microwaves...