麻豆村

Without the ability to control infrared light waves, autonomous vehicles wouldn鈥檛 be able to quickly map their environment and keep 鈥渆yes鈥� on the cars and pedestrians around them; augmented reality couldn鈥檛 display realistic 3D displays; doctors would lose an important tool for early cancer detection. Dynamic light control allows for upgrades to many existing systems, but complexities associated with fabricating programmable thermal devices hinders availability.

A new active metasurface, the electrical-programmable graphene field effect transistor (Gr-FET), from the labs of and in 麻豆村鈥檚 , enables the control of mid-infrared states across a wide range of wavelengths, directions, and polarizations. This enhanced control enables advancements in applications ranging from infrared camouflage to personalized health monitoring.

鈥淔or the first time, our active metasurface devices exhibited the monolithic integration of the rapidly modulated temperature, addressable pixelated imaging, and resonant infrared spectrum.鈥� said Xiu Liu, postdoctoral associate in mechanical engineering and lead author of the paper published in Nature Communications. 鈥淭his breakthrough will be of great interest to a wide range of infrared photonics, materials science, biophysics, and thermal engineering audiences.鈥�

The two-dimensional device is made up of gold array pixels that either directly interface with a single graphene layer or are separated by an insulation layer.

Video: Dynamic thermal mapping capture of experimental pixel sweeping of the pixelated 2D metasurface array illuminating each pixel sequentially and following a letter 鈥淟鈥� shape.

鈥淚t has low crosstalk, meaning the signals transmitted from one channel do not interfere with another,鈥� said Zexiao Wang, Ph.D. candidate in mechanical engineering, 鈥淭his breakthrough allows for scalable 2D electrical writing for densely packed, independently addressable pixels.鈥�

Tianyi Huang, also a Ph.D. candidate in mechanical engineering, led the development of a specially-designed circuit that powers the device. This allows the device to operate on its own or integrate into existing products.

鈥淭his device is scalable. It could be used on a chip to prevent side channel attacks by camouflaging existing thermal emission with misleading, programmed emissions. On the other side it could be worn in a garment to detect breast cancer cells,鈥� explained mechanical engineering Ph.D. candidate Yibai Zhong.

Side channel attacks are a way to exploit sensitive information, like encryption keys, by analyzing subtle temperature variations caused by computing device operations. By monitoring temperature fluctuations with a thermal imaging camera, an attacker can potentially piece together information. Shen鈥檚 device could act as an added level of security by camouflaging thermal emissions.

鈥淲e aren鈥檛 too far off from seeing this technology integrated into our lives,鈥� said Shen. 鈥淲e could be using it in the next five to 10 years.鈥�