Ultrathin tunable terahertz absorber based on MEMS-driven metamaterial

摘要

A material that can alter its interaction with long-wavelength radiation is constructed by researchers in Australia and the United States. Mingkai Liu et al. have created a structure with electrically tunable terahertz absorption. Terahertz light with wavelengths from 0.1 to 1 millimeter is useful in a variety of applications including security-screening. To improve current technologies, materials with a strong and tunable response are desired. The researchers used a microelectromechanical system (MEMS) to control terahertz absorption in a metamaterial — an array of sub-wavelength structures, the dimensions of which determine how the material interacts with electromagnetic waves. The geometry of the structure realized by the team led by Ilya Shadrivov (Australian National University) and Mariusz Martyniuk (University of Western Australia) is adaptively controlled by applying a voltage, rapidly changing the material terahertz absorption by up to 65%.