Enhancing the transmission properties of tunable metamaterials based on Dirac semimetals

摘要

In this paper, a tunable metamaterial based on plasmon induced transparency (PIT) with Dirac semimetal is designed and simulated. A transmission peak is achieved at resonance frequency 1.02 THz, the transmission peak is 80.2%. This transmission peak is excited by the bright-bright mode coupling effect distributed on edges of Dirac semimetal. By reducing the structural parameter a, a new transmission band (between 1.81THz-1.87 THz, the average transmittance reaches 93.4%) is achieved. By reducing the structural parameter b, another new transmission band (between 2.04THz and 2.24 THz, and the average transmittance reaches 95.1%) can be revealed. These new transmission bands are both based on the hybridization effect of bright modes. Transmission peak is shifted to higher frequencies with Fermi energy increasing. Moreover, the transmission properties of this tunable metamaterials can be controlled by increasing the intensity of horizontal or vertical magnetic field. By calculating the group delay in the transmission window range, it is found that the slow light effect is revealed in the transmission peak range.