Enhancement of a tunable single-band metamaterial absorber based on bright-bright modes coupling effect in terahertz range

In this paper, a Dirac semimetal-based tunable single-band metamaterial absorber is revealed at terahertz frequencies and it obtains a bright-bright modes coupling absorption peak with 92% amplitude at resonance frequency . This absorption peak is enhanced to 96% and shifted to lower frequencies when the structural parameter V is reduced to 12 . On the other hand, the absorption peak is enhanced to 95% and shifted to higher frequencies when the structural parameter H is reduced to 12 . New absorption bands are achieved when structural parameters V=10 or H=10 . When Fermi energy is increased from 55meV to 75meV, this absorption peak is shifted from 3.42THz to 4.16THz. When the strength of parallel or vertical magnetic fields is increased from 0.0T to 4.0T, this absorption peak is shifted to higher and lower resonance frequencies, respectively. This proposed tunable single-band metamaterial absorber shows the potential applications in optical sensing.