Gas Sensing with Bare and Graphene-covered Optical Nano-Antenna Structures

Abstract

The motivation behind this work is to study the gas phase chemical sensing characteristics of optical (plasmonic) nano-antennas (ONA) and graphene/graphene oxide-covered versions of these structures. ONA are devices that have their resonating frequency in the visible range. The basic principle governing the detection mechanism for ONA is refractive index sensing. The change in the concentration of the analyte results in a differing amount of adsorbate and correlated shifts in the resonance wavelength of the device. In this work, bare and graphene or graphene oxide covered ONA have been evaluated for gas sensing performance. Four different analytes (ethanol, acetone, nitrogen dioxide and toluene) were used in testing. ONA response behavior to different analytes was modified by adsorption within the graphene and graphene oxide overlayers. This work is a preliminary study to understand resonance wavelength shift caused by different analytes. Results imply that the combination of well-structured ONA functionalized by graphene-based adsorbers can give sensitive and selective sensors but baseline drift effects identified in this work must be addressed for applied measurements.

High‐Temperature Large‐Scale Self‐Assembly of Highly Faceted Monocrystalline Au Metasurfaces

“…Enhancing the sensitivity of LSPR optical gas sensors has been pursued by many approaches including the integration of catalytic reactive layers, 2D materials, or photonic crystal . Here, to further explore the potential of these highly faceted Au monocrystalline nanoislands, we implement a very recent strategy relying on the nanotexturing of plasmonic metasurfaces with highly porous fractal layers .…”

Determination of dynamic variations in the optical properties of graphene oxide in response to gas exposure based on thin-film interference

“…It can be observed that the f η values of GO increased over time as it was exposed to the gas for longer and longer times. This is expected because the large number of functional groups at the GO surface can effectively capture the gas molecules which enhances the RI of GO [30,31]. In the beginning, for each wavelength, the rate of increase of f η was high.…”

A Review on the Development of Tunable Graphene Nanoantennas for Terahertz Optoelectronic and Plasmonic Applications

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“…The work reported in [12] provided enhanced efficiency of the photoconductive antenna using hybrid graphene molybdenum disulfide structure and achieved broad reconfigurability in the THz range. Moreover, graphene in the THz range offers low loss surface plasmon propagation, which endeavors fewer losses than the metallic THz antennas [13]. This property of graphene tunable antennas provides an enhancement in the THz emissions.The design of optical nanoantenna is analogous to conventional microwave-and millimeter-wave antennas, as it controls the energy conversion of light into localized energy and optical radiation at the subwavelength scale [14].…”

“…The work reported in [12] provided enhanced efficiency of the photoconductive antenna using hybrid graphene molybdenum disulfide structure and achieved broad reconfigurability in the THz range. Moreover, graphene in the THz range offers low loss surface plasmon propagation, which endeavors fewer losses than the metallic THz antennas [13]. This property of graphene tunable antennas provides an enhancement in the THz emissions.…”