High-contrast terahertz wave modulation by gated graphene enhanced by extraordinary transmission through ring apertures.
Gate-controllable transmission of terahertz (THz) radiation makes graphene a promising material for making high-speed THz wave modulators. However, to date, graphene-based THz modulators have exhibited only small on/off ratios due to small THz absorption in single-layer graphene. Here we demonstrate a ∼50% amplitude modulation of THz waves with gated single-layer graphene by the use of extraordinary transmission through metallic ring apertures placed right above the graphene layer. The extraordinary transmission induced ∼7 times near-filed enhancement of THz absorption in graphene. These results promise complementary metal-oxide-semiconductor compatible THz modulators with tailored operation frequencies, large on/off ratios, and high speeds, ideal for applications in THz communications, imaging, and sensing.
Department of Electrical and Computer Engineering, ‡Department of Materials Science and NanoEngineering, and §Department of Physics and Astronomy, Rice University , Houston, Texas 77005, United States.
Weilu
W
Gao
Jie
J
Shu
Kimberly
K
Reichel
Daniel V
DV
Nickel
Xiaowei
X
He
Gang
G
Shi
Robert
R
Vajtai
Pulickel M
PM
Ajayan
Junichiro
J
Kono
Daniel M
DM
Mittleman
Qianfan
Q
Xu