Broadband terahertz modulators using self-gated graphene capacitors
Date
2015
Authors
Kakenov, N.
Balci, O.
Polat, E. O.
Altan, H.
Kocabas, C.
Editor(s)
Advisor
Supervisor
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Instructor
Source Title
Journal of the Optical Society of America B: Optical Physics
Print ISSN
0740-3224
Electronic ISSN
Publisher
Optical Society of America
Volume
32
Issue
9
Pages
1861 - 1866
Language
English
Type
Journal Title
Journal ISSN
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Abstract
We demonstrate a terahertz intensity modulator using a graphene supercapacitor which consists of two large-area graphene electrodes and an electrolyte medium. The mutual electrolyte gating between the graphene electrodes provides very efficient electrostatic doping with Fermi energies of 1 eV and a charge density of 8 × 1013 cm-2. We show that the graphene supercapacitor yields more than 50% modulation between 0.1 and 1.4 THz with operation voltages less than 3 V. The low insertion losses, high modulation depth over a broad spectrum, and the simplicity of the device structure are the key attributes of graphene supercapacitors for THz applications.