Phys.org February 28, 2022 Researchers at the South Florida University have demonstrated a high-efficiency RF energy harvesting device based on a metamaterial perfect absorber (MPA). With the embedded Schottky diodes, the MPA-based rectenna converts captured RF waves to DC power. The Fabry-Perot (FP) cavity resonance of the MPA greatly improved the amount of energy captured. The FP resonance exhibited a high Q-factor and significantly increased the voltage across the Schottky diodes, which improved the rectification efficiency, particularly at low intensity. This led to a factor of 16 improvement of RF-DC conversion efficiency at ambient intensity level. According to the researchers […]
Tag Archives: Meta materials
Deep learning and metamaterials make the invisible visible
Nanowerk August 11, 2020 Due to the diffraction limit seeing and recognizing an object whose size is much smaller than the illumination wavelength is a challenging task for an observer placed in the far field. Researchers in Switzerland have demonstrated that combining deep learning with lossy metalenses allows recognizing and imaging largely subwavelength features directly from the far field. Their acoustic learning experiment shows that, despite being 30 times smaller than the wavelength of sound, the fine details of images can be successfully reconstructed and recognized in the far field, which is crucially favored by the presence of absorption. They […]
Smart metamaterials that sense and reprogram themselves
Phys.com November 11, 2019 As proof of concept, an international team of researchers (USA – Duke University, UK, China) proposed and developed a smart digital-coding metasurface with self-adaptive capacity for reprogrammable functionality. A sensor on the metasurface detected specific features surrounding the construct in the environment and delivered them to a microcontroller unit (MCU) which independently determined reactions to these variations and then instructed the FPGA via coding patterns, to change the metasurface configuration in real time. The smart metasurfaces achieved self-adaptive reprogrammable functionality automatically based on the surface-installed sensing-feedback system and calculation software. The team envisions the preliminary work […]