Enhanced tunability of V-shaped plasmonic structures using ionic liquid gating and graphene
Date
2016Source Title
Carbon
Print ISSN
0008-6223
Publisher
Elsevier Ltd
Volume
108
Pages
515 - 520
Language
English
Type
ArticleItem Usage Stats
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Abstract
Graphene is a strong candidate for active optoelectronic devices because of its electrostatically tunable optical response. Current substrate back-gating methods are unable to sustain high fields through graphene unless a high gate voltage is applied. In order to solve this problem, ionic liquid gating is used which allows substrate front side gating, thus eliminating the major loss factors such as a dielectric layer and a thick substrate layer. On the other hand, due to its two dimensional nature, graphene interacts weakly with light and this interaction limits its efficiency in optoelectronic devices. However, V-shaped plasmonic antennas can be used to enhance the incident electric field intensity and confine the electric field near graphene thus allowing further interaction with graphene. Combining V-shaped nanoantennas with the tunable response of graphene, the operation wavelength of the devices that utilize V-shaped antennas can be tuned in situ. In the present paper, we demonstrate a graphene-based device with ionic liquid gating and V- shaped plasmonic antennas to both enhance and more effectively tune the total optical response. We are able to tune the transmission response of the device for up to 389 nm by changing the gate voltage by 3.8 V in the mid-infrared regime.
Keywords
AntennasElectric fields
Graphene
Ionic liquids
Liquids
Optoelectronic devices
Plasmons
Reconfigurable hardware
Threshold voltage
Dielectric layer
Electric field intensities
Its efficiencies
Operation wavelength
Optical response
Thick substrates
Transmission response
Two dimensional nature
Graphene devices