Self-biased reconfigurable graphene stacks for terahertz plasmonics.
The gate-controllable complex conductivity of graphene offers unprecedented opportunities for reconfigurable plasmonics at terahertz and mid-infrared frequencies. However, the requirement of a gating electrode close to graphene and the single 'control knob' that this approach offers limits the practical implementation and performance of these devices. Here we report on graphene stacks composed of two or more graphene monolayers separated by electrically thin dielectrics and present a simple and rigorous theoretical framework for their characterization. In a first implementation, two graphene layers gate each other, thereby behaving as a controllable single equivalent layer but without any additional gating structure. Second, we show that adding an additional gate allows independent control of the complex conductivity of each layer within the stack and provides enhanced control on the stack equivalent complex conductivity. These results are very promising for the development of THz and mid-infrared plasmonic devices with enhanced performance and reconfiguration capabilities.
1] Adaptive MicroNano Wave Systems, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland [2] Department of Electrical and Computer Engineering, University of Texas at Austin, Guadalupe 1616, 1 University Station C0803, Austin, Texas 78712, USA.
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JS
Gomez-Diaz
Nanoelectronics Devices Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
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C
Moldovan
Laboratory of Electromagnetics and Acoustics (LEMA), École Polytechnique Fédérale de Lausanne, Lausanne 1015, Switzerland.
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S
Capdevila
AntenaLAB, Universitat Politcnica de Catalunya, C/Jordi Girona 1-3, Barcelona 08034, Spain.
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Romeu
Laboratory of Physics and Complex Matter, École Polytechnique Fédérale de Lausanne, Lausanne 1015, Switzerland.
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LS
Bernard
Crystal growth facility, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
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A
Magrez
Nanoelectronics Devices Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
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AM
Ionescu
Adaptive MicroNano Wave Systems, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
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Perruisseau-Carrier