An electric current will not only heat a hybrid metamaterial, but will also trigger it to change state and fade into the background like a chameleon in what may be the proof-of-concept of the first controllable metamaterial device, or metadevice, according to a team of engineers.
“Previous metamaterials work focused mainly on cloaking objects so they were invisible in the radio frequency or other specific frequencies,” said Douglas H. Werner, John L. and Genevieve H. McCain Chair Professor of electrical engineering, Penn State. “Here we are not trying to make something disappear, but to make it blend in with the background like a chameleon and we are working in optical wavelengths, specifically in the infrared.”
Metamaterials are synthetic, composite materials that possess qualities not seen in natural materials. These composites derive their functionality by their internal structure rather than by their chemical composition. Existing metamaterials have unusual electromagnetic or acoustic properties. Metadevices take metamaterials and do something of interest or value as any device does.
“The key to this metamaterial and metadevice is vanadium dioxide, a phase change crystal with a phase transition that is triggered by temperatures created by an electric current,” said Lei Kang, research associate in electrical engineering, Penn State.
The metamaterial is composed of a base layer of gold thick enough so that light cannot pass through it. A thin layer of aluminum dioxide separates the gold from the active vanadium dioxide layer. Another layer of aluminum dioxide separates the vanadium from a gold-patterned layer that is attached to an external electric source. The geometry of the patterned mesh screen controls the functional wavelength range. The amount of current flowing through the device controls the Joule heating effect, the heating due to resistance.
“The proposed metadevice integrated with novel transition materials represents a major step forward by providing a universal approach to creating self-sufficient and highly versatile nanophotonic systems,” the researchers said in today’s (Oct. 27) issue of Nature Communications.
As a proof of concept, the researchers created a .035 inch by .02 inch device and cut the letters PSU into the gold mesh layer so the vanadium dioxide showed through. The researchers photographed the device using an infrared camera at 2.67 microns. Without any current flowing through the device, the PSU stands out as highly reflective. With a current of 2.03 amps, the PSU fades into the background and becomes invisible, while at 2.20 amps, the PSU is clearly visible but the background has become highly reflective.
The response of the vanadium dioxide is tunable by altering the current flowing through the device. According to the researchers, vanadium dioxide can change state very rapidly and it is the device configuration that limits the tuning.
Learn more: Metamaterial device allows chameleon-like behavior in the infrared
The Latest on: Controllable metamaterial device
[google_news title=”” keyword=”Controllable metamaterial device” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
via Google News
The Latest on: Controllable metamaterial device
- The Best Smart Assistive Devices for People With Disabilitieson April 26, 2024 at 1:25 pm
Automation, scheduling, and voice control enable users to easily control a host of devices—from lights and switches to climate-control systems and fans to window coverings and media devices ...
- Best streaming devices in 2024on April 19, 2024 at 12:06 pm
The other reason why we prefer buying a streaming device is to control the interface, as most television purchases stick you with something you can't control. Roku OS and Apple's tvOS offer ...
- The Best Streaming Devices for 2024on April 8, 2024 at 9:10 am
It features Google Assistant for voice control of not only the Chromecast but smart home devices as well. Just get ready to power this device with its own adapter, as it requires more juice than ...
- Google finally launches its Find My Device networkon April 7, 2024 at 5:00 pm
Google's Find My Device network is rolling out today, prioritizing privacy with encrypted location data and limitations on tracking in private locations like homes. Android users can control their ...
- One control panel for all your home devices is still a lot to askon April 2, 2024 at 6:07 pm
Gift 5 articles to anyone you choose each month when you subscribe. Hello, and welcome to the latest instalment of ‘Why On Earth?’ where we provide you with ready answers to the toughest ...
- Team demonstrates an ultra-broadband tunable terahertz absorber of graphene and hierarchical plasmonic metamaterialson April 1, 2024 at 12:56 pm
Compared to static passive physical systems, tunable metamaterials can dynamically manipulate electromagnetic waves, improving multidimensional control of the optical response. There are two ...
- Tired of many remotes? Here's the secret to controlling all your devices with one remote controlon March 28, 2024 at 2:34 pm
And all these devices have their own controls. You can of course purchase a universal remote control to control them all. Don't rush to spend money! Your TV may have a feature that not everyone knows ...
- The Best Smart Security Devices to Make Your New Home Feel Safeon February 1, 2024 at 11:13 pm
Before you begin adding any new gadgets, confirm whether your new home already has any smart devices installed. If so, and the previous owner hasn’t relinquished control of them, then that’s a ...
via Bing News