Open AccessDirac semimetals based tunable narrowband absorber at terahertz frequencies
Author(s) -
Guidong Liu,
Xiang Zhai,
Haiyu Meng,
Qi Lin,
Yu Huang,
Chujun Zhao,
Lingling Wang
Publication year - 2018
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.011471
Subject(s) - terahertz radiation , narrowband , optics , materials science , bandwidth (computing) , dielectric , physics , hfss , optoelectronics , telecommunications , antenna (radio) , computer science , microstrip antenna
In this paper, a bulk Dirac semimetals (BDSs) based tunable narrowband absorber at terahertz frequencies is proposed and it has the attractive property of being polarization-independent at normal incidence because of its 90° rotational symmetry. Numerical results show that the absorption bandwidth is about 1.469e-2 THz and the total quality factor Q, defined as Q = f 0 /Δf, reaches about 94.6, which can be attributed to the low power loss of the guided mode resonance in the dielectric layer. The simulation results are analyzed with coupled mode theory. Interestingly, on the premise of maintaining the absorbance at a level greater than 0.95, the absorption frequency can be tuned from 1.381 to 1.395 THz by varying the Fermi energy of BDSs from 50 to 80 meV. Our results may also provide potential applications in optical filter and bio-chemical sensing.