A Band-Switchable and Tunable THz Metamaterial Based on an Etched Vanadium Dioxide Thin Film

Jun-Hwan Shin,Kyung Hyun Park,Han-Cheol Ryu

doi:10.3390/photonics9020089

Jun-Hwan Shin, Kyung Hyun Park + Show 1 more

Open Access

https://doi.org/10.3390/photonics9020089

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Abstract

A band-switchable and tunable terahertz (THz) metamaterial based on a vanadium dioxide (VO2) thin film was proposed in the THz frequency regime. The VO2 thin film with a high conductivity change rate and smooth phase transition characteristics was deposited. To obtain band switching characteristics and reduce THz wave loss, the VO2 thin film was etched in the form of a line. Two rectangular C-shaped resonators were configured to face each other, with an etched VO2 thin film line in between. When the VO2 thin film was in the insulator phase, the two resonators individually resonated, and when the VO2 thin film was in the metal phase, they were connected and resonated as one, showing band switching characteristics. According to the state of the VO2 thin film, the fabricated metamaterial resonated at 1.29 THz when the two resonators were electrically separated and resonated at 0.65 THz when the two resonators were electrically connected. In the band-switching process, the THz wave transmission characteristics were continuously tunable. The measurement results of the proposed structure clearly showed that the rectangular C-shaped metamaterial based on the etched VO2 thin film is capable of band switching and continuous transmission control. In the near future, band-switchable and tunable THz metamaterials based on etched VO2 thin films can be employed as key devices in THz wave 6G wireless communication technology.

Highlights

Terahertz (THz) technology has received considerable interest because of its potential application in various fields such as wireless communications, spectroscopy, imaging, and sensing [1–4]
We propose a band-switchable and tunable THz metamaterial based on VO2 thin films
We proposed a band-switchable and tunable THz metamaterial based on an etched vanadium dioxide (VO2 ) thin film

Summary

Introduction

Terahertz (THz) technology has received considerable interest because of its potential application in various fields such as wireless communications, spectroscopy, imaging, and sensing [1–4]. The dielectric properties of the VO2 thin film-based metamaterial substrate can be controlled by the phase transition of the VO2 thin film, thereby controlling the resonance properties of the metamaterial. It is a viable candidate for the development of THz tunable devices because it provides superior modulation and switching characteristics in the wideband THz region, owing to the rapid generation characteristics of free carriers undergoing a phase transition. THz VO2 thin films were grown with smooth phase transition properties and high rates of change for band switching and continuously tunable metamaterial applications. The proposed etched VO2 -based THz metamaterial exhibited a band switching characteristic while continuously changing its transmittance characteristics

Materials

O3 for alignment along the VO

Design and Simulation

This is becauseof the metamaterial of the two re

Surface density of a band-switchable and tunable THz

Conclusions