Dynamically tunable terahertz quadruple-function absorber based on a hybrid configuration of graphene and vanadium dioxide

Abstract

A quadruple-function dynamically tunable terahertz absorber that uses a hybrid configuration of graphene and vanadium dioxide is proposed in this paper. The absorber achieves dynamic conversion of four functions in one structure: ultra-broadband, broadband, single-frequency narrowband and dual-frequency narrowband, by utilizing the electrical control properties of graphene and the phase-shifting properties of vanadium dioxide. Furthermore, the paper also reveals the physical mechanism of the proposed absorber through the electric field distribution and impedance matching theory. In addition, the influences of the Fermi energy level of graphene and the electrical conductivity of vanadium dioxide on the absorption spectra are investigated, demonstrating the structure’s dynamic tunability. Due to the above features, the designed absorber is expected to have potential applications in terahertz imaging, modulation and filtering.

VO2-Graphene Ultrathin Films: Enabling Wideband Switchable and Tunable THz Absorption

“…Additionally, advanced experimental setups may incorporate temperature sensors and feedback control mechanisms to monitor and maintain the desired temperature of the VO 2 sample throughout the experiment. This ensures stable conditions for studying the phase change behavior and its practical implications [37], [38], [39], [40], [41]. Also, advanced characterization techniques, such as scanning electron microscopy (SEM) and atomic force microscopy (AFM), are often employed to assess the structural integrity and performance of the fabricated absorber, validating its suitability for THz frequency applications.…”

Dynamic switching: vanadium dioxide and graphene-based terahertz perfect absorber for tunable broadband absorption and tri-band absorption

“…Regarding broadband studies, many research groups have achieved successful results by stacking dielectric and metal layers in a sequential manner, resulting in broadband PA absorbers [19][20][21]. Furthermore, the rapid development of electronics and materials has led to the utilization of tunable absorber materials, such as black phosphorus [22], liquid crystals [23], graphene [24][25][26][27][28][29][30][31][32], and VO 2 [33][34][35][36], in this field.…”