Gizmorama - February 26, 2018

Good Morning,

Those with prosthetic limbs are getting closer to regaining the ability to touch and feel with the development of sensitive stretchable electronic skin.

Learn about this and more interesting stories from the scientific community in today's issue.

Until Next Time,
Erin

P.S. Did you miss an issue? You can read every issue from the Gophercentral library of newsletters on our exhaustive archives page. Thousands of issues, all of your favorite publications in chronological order. You can read AND comment. Just click GopherArchives



*-- Upside-down light: Scientists invert optical waves --*
Scientists in Spain have developed a new material, a so-called hyperbolic metasurface, that inverts light waves. The technology could give researchers more precise control of optical waves and could be incorporated into a variety of optical devices.

Normally light waves propagate outward in circular, or convex, wavefronts from its source, like the ripple from a stone tossed into water. The behavior is explained by light's normal medium, homogeneous and isotropic, the same in all directions.

Scientists theorized that light waves propagated along specially engineered surfaces would produce inverted optical waves.

"On such surfaces, called hyberbolic metasurfaces, the waves emitted from a point source propagate only in certain directions, and with open, or concave, wavefronts," Javier Alfaro, a PhD student at the nanoGUNE Cooperative Research Center in Basque, said in a news release.

Because the metasurface constrains the paths of the lightwaves, the wavelengths are much smaller and only propagate in certain directions. Scientists call the unique lightwaves hyperbolic surface polaritons.

As part of their latest research efforts, scientists at nanoGUNE created a new kind of hyperbolic metasurface made from boron nitride. The 2D graphene-like material is designed to convert infrared lightwaves into hyperbolic surface polaritons. The technology could be used in tiny sensors and other nanoscale optoelectronic devices.

To build their new hyperbolic metasurface, scientists used electron beam lithography technology to finely etch nanoscale textures onto ultra thin flakes of boron nitride.

"The same fabrication methods can also be applied to other materials, which could pave the way to realize artificial metasurface structures with custom-made optical properties," said researcher Saül Vélez.

Scientists used a scattering-type scanning near-field microscope to image the waves created when light was propagated across their newly fabricated hyperbolic metasurface.

"It was amazing to see the images," said nanGUNE professor Rainer Hillenbrand. "They indeed showed the concave curvature of the wavefronts that were propagating away form the gold nanorod, exactly as predicted by theory."

Scientists described their efforts in a new paper published this week in the journal Science.



*-- New stretchable electronic skin sensitive enough to feel ladybug footsteps --*
People with prosthetic limbs live without the ability to touch and feel the world around them. That could change in the near future thanks to new technology developed by scientists at Stanford University.

As described in a newly published Nature paper, researchers have developed stretchable electronic skin sensitive enough to feel the footsteps of an artificial ladybug.

The artificial skin's physical attributes are impressive, but the study's biggest breakthrough might be the new techniques used to produce the novel polymer. Scientists developed a more efficient and scalable method for creating electronic skin.

"Research into synthetic skin and flexible electronics has come a long way, but until now no one had demonstrated a process to reliably manufacture stretchable circuits," Stanford chemical engineer Zhenan Bao said in a news release.

The new artificial skin is formed by layers of hi-tech polymers. Some layers enhance the skin's elasticity. Other layers feature the electronic meshing that allows the circuitry to be embedded in the skin. Still more layers help insulate the electronic components and provide waterproofing.

"We've engineered all of these layers and their active elements to work together flawlessly," said post-doctoral researcher Sihong Wang.

The skin can stretch to twice its size without impacting the sensors embedded in the polymer layers.

Scientists hope the new layering approach will pave the way for the production of polymers with all kinds of embedded electronic circuits and sensors. While researchers say they need to improve upon the speed of the current prototype's electronic system, scientists are confident the technology could soon replace more rigid electronic components and circuitry.

And though complete artificial skin may still be a ways off, the technology could soon be used to install elastic touch screens for use in smart clothing, wearable electronics or medical devices.

"I believe we're on the verge of a whole new world of electronics," Bao said.

***
Missed an Issue? Visit the Gizmorama Archives