{"id":6072,"date":"2016-03-08T08:14:51","date_gmt":"2016-03-08T08:14:51","guid":{"rendered":"http:\/\/www.kurzweilai.net\/?p=275245"},"modified":"2016-03-08T10:27:52","modified_gmt":"2016-03-08T10:27:52","slug":"stretchable-flexible-meta-skin-cloaks-objects-from-radar-at-a-range-of-frequencies","status":"publish","type":"post","link":"https:\/\/hoo.central12.com\/fugic\/2016\/03\/08\/stretchable-flexible-meta-skin-cloaks-objects-from-radar-at-a-range-of-frequencies\/","title":{"rendered":"Stretchable, flexible ‘meta-skin’ cloaks objects from radar at a range of frequencies"},"content":{"rendered":"
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Flexible, stretchable, and frequency-tunable “meta-skin” can trap radar waves and cloak objects from radar detection (scale bars: 5 mm) (credit: Siming Yang et al.\/Scientific Reports)<\/p><\/div>\n

Iowa State University\u00a0engineers<\/a> have developed a new flexible, stretchable, and \u00a0tunable \u201cmeta-skin\u201d (metamaterial<\/a>) “invisibility cloak” that uses rows of small liquid-metal devices to cloak an object from radar over a wide range of frequencies — and possibly at visible or infrared light ranges in the future.<\/p>\n

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First wraparound meta-skin (credit: Siming Yang et al.\/Scientific Reports)<\/p><\/div>\n

The\u00a0 skin has rows of split ring resonators<\/a> embedded inside layers of silicone sheets. The resonators are filled with galinstan, a metal alloy that\u2019s liquid at room temperature. That allows for stretching and flexing the polymer meta-skin, enabling it to be tuned to reduce reflection at a wide range of radar frequencies, unlike previous metamaterials.<\/p>\n

Applications could include sub-wavelength imaging (of smaller objects), electromagnetic frequency tuning, shielding (from interference or detection), and scattering suppression (allowing a signal to be sent in specific directions rather than scattered).<\/p>\n

Unlike conventional metamaterials, meta-skin can be conformed to curved and irregular surfaces.<\/p>\n

The split-ring resonators used here are small rings with an outer radius of 2.5 millimeters and a thickness of half a millimeter. They have a 1 millimeter gap, essentially creating a small, curved segment of liquid wire.<\/p>\n

The rings create electric inductors and the gaps create electric capacitors. Together they create a tuned resonator that can trap and suppress radar waves at a specific frequency. Stretching the meta-skin changes the size of the liquid metal rings inside and lowers the frequency the devices suppress.<\/p>\n

Tests showed radar suppression was about 75 percent in the frequency range of 8 to 10 gigahertz in the experiment, according to the paper. When objects are wrapped in the meta-skin, the radar waves were suppressed in all incident directions and observation angles.<\/p>\n

The open-access journal Scientific Reports<\/em>\u00a0recently reported the discovery online.<\/p>\n

\u201cThe long-term goal is to shrink the size of these devices,\u201d said senior author and associate professor Liang Dong, allowing for use with higher-frequency electromagnetic waves such as visible or infrared light. That would require advanced nanomanufacturing technologies and appropriate structural modifications, Dong noted.<\/p>\n

The National Science Foundation and the China Scholarship Council partially supported the project.<\/p>\n

\n

Abstract of\u00a0From Flexible and Stretchable Meta-Atom to Metamaterial: A Wearable Microwave Meta-Skin with Tunable Frequency Selective and Cloaking Effects<\/em><\/h4>\n

This paper reports a flexible and stretchable metamaterial-based \u201cskin\u201d or meta-skin with tunable frequency selective and cloaking effects in microwave frequency regime. The meta-skin is composed of an array of liquid metallic split ring resonators (SRRs) embedded in a stretchable elastomer. When stretched, the meta-skin performs as a tunable frequency selective surface with a wide resonance frequency tuning range. When wrapped around a curved dielectric material, the meta-skin functions as a flexible \u201ccloaking\u201d surface to significantly suppress scattering from the surface of the dielectric material along different directions. We studied frequency responses of multilayer meta-skins to stretching in a planar direction and to changing the spacing between neighboring layers in vertical direction. We also investigated scattering suppression effect of the meta-skin coated on a finite-length dielectric rod in free space. This meta-skin technology will benefit many electromagnetic applications, such as frequency tuning, shielding, and scattering suppression.<\/p>\n","protected":false},"excerpt":{"rendered":"

Iowa State University engineers have developed a new flexible, stretchable, and  tunable “meta-skin” (metamaterial) “invisibility cloak” that uses rows of small liquid-metal devices to cloak an object from radar over a wide range of frequencies — and possibly at visible or infrared light ranges in the future. The  skin has rows of split ring resonators embedded […]<\/p>\n","protected":false},"author":13,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[48,55,43],"tags":[],"class_list":["post-6072","post","type-post","status-publish","format-standard","hentry","category-electronics","category-nanotechmaterials-science","category-news"],"_links":{"self":[{"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/posts\/6072"}],"collection":[{"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/users\/13"}],"replies":[{"embeddable":true,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/comments?post=6072"}],"version-history":[{"count":2,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/posts\/6072\/revisions"}],"predecessor-version":[{"id":6077,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/posts\/6072\/revisions\/6077"}],"wp:attachment":[{"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/media?parent=6072"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/categories?post=6072"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/tags?post=6072"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}