A dynamically tunable terahertz metamaterial absorber with switching characteristics and excellent absorption combining Dirac semimetal and vanadium dioxide

For the terahertz band, in this paper, we theoretically propose an absorber that integrated Dirac Semimetal (BDS) and Vanadium Dioxide (VO2) smoothly into together. The dynamic connection between the conductivity of the Dirac semimetal and the Fermi level gives our absorber dynamic tunable properties. On the other side, with the continuous increase of VO2 temperature, its conductivity also changed dramatically, the variation value of close to 3 similar to 4 orders of magnitude, which push VO2 Change reversibly from the metal state to the insulating state. This feature gives our absorbers a flexible, adjustable and reversible switching function. We used frequency-domain finite element decomposition algorithm to simulate, analyze and calculate the absorption performance of the absorber in the extent of terahertz band. The results show that there are two excellent bone absorption at 4.804THzand 7.364THz, and the absorption rates are above 95 %, at 95.65 % and 99.89 % respectively. We also analyzed the variation of the structural parameters of the absorber with its absorption, when the absorber is open, and the results proved the rationality of the structural parameters we designed. Finally, in order to discuss its working condition in different environments, we also calculated its refractive index sensitivity (S). Our work provides a new idea for the study of THz absorbers. Meanwhile, also offered a proposal for the multiple meta -materials conjunction with absorber and the design of new switches.