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Updated: May 26, 2026

Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
Active microwave negative-index metamaterial transmission line with gain
Tao Jiang1, Kihun Chang, Li-Ming Si
1Department of Information Science and Electronic Engineering, Zhejiang University, Hangzhou, People's Republic of China.
Abstract:
We studied the active metamaterial transmission line at microwave frequency. The active composite right-handed or left-handed transmission line was designed to incorporate a germanium tunnel diode with a negative differential resistance property as the gain device at the unit cell level. Measurements of the fabricated planar transmission line structures with one-, two-, and three-unit cells showed that the addition of the dc pumped tunnel diodes not only provided gain but also maintained the left handedness of the transmission line metamaterial. Simulation results agree well with experimental observation. This work demonstrated that negative index material can be obtained with a net gain when an external source is incorporated.
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