Reconfigurable Bowtie Antenna Using Metal-Insulator Transition in Vanadium Dioxide

Abstract

A new method to reconfigure, tune or program an antenna is presented and validated through a fabricated proof-of-concept prototype. The method relies on the changing electrical properties of a smart material, vanadium dioxide ( VO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ), across its solid-to-solid phase transition. The phase change in the material is induced thermally. The developed device is a monolithically integrated VO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> -based antenna that changes resonant frequency on demand. Details and challenges related to the design, fabrication and integration of VO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> thin films with antennas, as well as the measurement setup, are discussed. Measurement results match well with theory and simulations. Results unveil a new technique for reconfiguring antennas and suggest further studies and improvements could lead to more exciting results and make vanadium dioxide thin-films an alternate solution for multi-functional antennas. This work is the first prototype to implement this new reconfiguration mechanism in antennas in the gigahertz range and to present results during the VO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> metal-to-insulator phase transition.