Abstract-Terahertz dual-band metamaterial absorber based on graphene/MgF2multilayer structures

Terahertz dual-band metamaterial absorber based on graphene/MgF2multilayer structures Zhaoxian Su, Jianbo Yin, and Xiaopeng Zhao  »View Author Affiliations

Optics Express, Vol. 23, Issue 2, pp. 1679-1690 (2015)
http://dx.doi.org/10.1364/OE.23.001679

http://www.opticsinfobase.org/oe/abstract.cfm?uri=oe-23-2-1679

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We design an ultra-thin terahertz metamaterial absorber based on graphene/MgF₂ multilayer stacking unit cells arrayed on an Au film plane and theoretically demonstrate a dual-band total absorption effect. Due to strong anisotropic permittivity, the graphene/MgF₂ multilayer unit cells possess a hyperbolic dispersion. The strong electric and magnetic dipole resonances between unit cells make the impedance of the absorber match to that of the free space, which induces two total absorption peaks in terahertz range. These absorption peaks are insensitive to the polarization and nearly omnidirectional for the incident angle. But the absorption intensity and frequency depend on material and geometric parameters of the multilayer structure. The absorbed electromagnetic waves are finally converted into heat and, as a result, the absorber shows a good nanosecond photothermal effect.

© 2015 Optical Society of America