We’ve talked about military-related research into invisibility cloaks on this blog before; now the Pentagon and some researchers at Cornell are looking at ways to mask entire events as they happen. The technology not only has implications for military operations, but also new types of light-based photonic chipsets.
The Cornell University researchers published a paper in Nature explaining how they managed to hide an event for 40 trillionths of a second. This spatio-temporal cloaking method slows down the flow of light from events, rendering them invisible. The research was funded by DARPA.
In the experiment, researchers split a beam of light traveling through a fiber-optic cable into one slow and one fast beam, then fired a red laser through the same space. The laser was not observable for several picoseconds. According to the article:
This approach is based on accelerating the front part of a probe light beam and slowing down its rear part to create a well controlled temporal gap—inside which an event occurs—such that the probe beam is not modified in any way by the event. The probe beam is then restored to its original form by the reverse manipulation of the dispersion. Continue reading
Here’s a development that could point the way toward the integration of textiles in electronic design: an international team of researchers have developed transistors made from cotton fibers that could allow sensor or processors to be incorporated directly into fibers and fabric. That’s right, it may soon be difficult to distinguish a design engineer from a fashion designer.
In order to make cotton conductive, the researchers coated the strands with gold nanoparticles, then added a thin layer of a conductive polymer called PEDOT. This increased conductivity approximately 1,000 times while leaving the fibers flexible.
If you think about how many fibers you have in your T-shirt, and how many interconnections you have between the weft and the warp of the fabric, you could get pretty decent computing power.
— Juan Hinestroza, director of the Textiles Nanotechnology Laboratory, Cornell.
Editor’s Note: This guest blog post is by Dr. Kingshuk Majumdar, associate professor of physics, Grand Valley State University, MI. Dr. Majumdar shares some of his research below, which was greatly facilitated via use of a supercomputing cluster. If you would like to contribute to Engineering on the Edge, please contact us.
Frustrated magnetic materials contain a wealth of interesting magnetic properties. Unlocking the mysteries of these frustrated magnets will not only deepen our understanding of the fundamental physics of these materials, but may also provide clues for potential technological applications in the near future. Therefore, these systems are presently under intense investigation by the physics community.
Besides mass and charge, the electron, an elementary particle within an atom, also has “spin.” Spin, an intrinsic property of electrons, comes in two varieties — “spin‐up” and “spin‐down.” In frustrated magnets, imbalance of these two types of spins results in magnetic frustration. With state‐of‐ the‐art 504 node supercomputing cluster “MATLAB on the TeraGrid” housed in Center for Advanced Computing at Cornell University, I am theoretically investigating the rich and exotic physics of these complex magnetic materials.