Adjustable and controllable metamaterial array design based on focused ion beam and MEMS (Micro-Electromechanical System) machining process

The invention discloses a method for preparing an adjustable and controllable metamaterial array based on a focused ion beam (FIB) and an MEMS (Micro-Electromechanical System) machining process, which can be applied to construction of planar optical components and is applied to the fields of communications, electromagnetic sensing and imaging (including micrometer wave, terahertz and infrared band ranges). The method has the advantages that (1) a suspension dual-metal resonant ring metamaterial array is machined through an MEMS process, the size of the array can be controlled at a micrometer grade and a sub-micrometer grade, and a resonant frequency of a negative refractive index characteristic can be on a millimeter wave, terahertz (THz) or infrared band; (2) stress is introduced into a fixed end of an inner resonant ring through FIB irradiation, and warping angles (between -40 degrees and +120 degrees) of suspension inner resonant ring structures in units of a metamaterial can be controlled accurately through control of an acceleration voltage, bombarding beam current, action time and an irradiation pattern of the FIB; and (3) a resonant frequency of a negative refractive index of the metamaterial array is adjustable, and an amplitude, a phase and an emitting direction of an electromagnetic wave can be controlled accurately through selection of machining parameters.