A simply accessed approach of 2D‐shaping liquid metal in microwave device applications

Abstract In this letter, a simply accessed approach of 2D‐shaping liquid metal (LM) is presented. This approach allows a microwave device to take advantage of LM in both stretchability and removability. This approach is achieved based on the Young–Laplace theory of liquid surface tension, as well as the surface oxidization that LM possesses. An application example of this approach is demonstrated by a functional changeable microwave device. The proposed device operates in antenna mode when LM is not incorporated. Then, it can change to resonator mode after filling 2D‐shaped LM into fluidic channels. To our knowledge, it is the first device that is capable of changing its function using LM. The measured gain of the proposed microwave device is 7.1 dBi at 2.68 GHz when it operates in antenna mode. The measured insertion loss of the proposed microwave is 1.8 dB at 2.62 GHz when it operates in resonator mode.