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Experimental demonstration of a transparent graphene millimetre wave absorber with 28% fractional bandwidth at 140 GHz.

Wu B, Tuncer HM, Naeem M, Yang B, Cole MT, Milne WI, Hao Y - Sci Rep (2014)

Bottom Line: Broadband absorption is a result of mutually coupled Fabry-Perot resonators represented by each graphene-quartz substrate.Millimetre wave reflectometer measurements of the stacked graphene-quartz absorbers demonstrated excellent broadband absorption of 90% with a 28% fractional bandwidth from 125-165 GHz.Our data suggests that the absorbers' operation can also be extended to microwave and low-terahertz bands with negligible loss in performance.

View Article: PubMed Central - PubMed

Affiliation: 1] School of Electronic Engineering and Computer Science, Queen Mary University of London, London, E1 4NS, United Kingdom [2] School of Electronic Engineering, Xidian University, Xi'an, 710071, China.

ABSTRACT
The development of transparent radio-frequency electronics has been limited, until recently, by the lack of suitable materials. Naturally thin and transparent graphene may lead to disruptive innovations in such applications. Here, we realize optically transparent broadband absorbers operating in the millimetre wave regime achieved by stacking graphene bearing quartz substrates on a ground plate. Broadband absorption is a result of mutually coupled Fabry-Perot resonators represented by each graphene-quartz substrate. An analytical model has been developed to predict the absorption performance and the angular dependence of the absorber. Using a repeated transfer-and-etch process, multilayer graphene was processed to control its surface resistivity. Millimetre wave reflectometer measurements of the stacked graphene-quartz absorbers demonstrated excellent broadband absorption of 90% with a 28% fractional bandwidth from 125-165 GHz. Our data suggests that the absorbers' operation can also be extended to microwave and low-terahertz bands with negligible loss in performance.

No MeSH data available.


Related in: MedlinePlus

Millimetre wave reflectometer measurements.(a) Photograph of the experimental set-up. Red lines refer to the incident wave from the transmitter to the sample; green lines represent the reflected wave from the sample to the receiver. The H-grating transmits vertically polarized waves but reflects horizontally polarized waves. The 45D grating selects the E-field components with 45° rotation. (b) Photograph of the transparent absorber consisting of graphene-quartz samples backed with a metal plate.
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f2: Millimetre wave reflectometer measurements.(a) Photograph of the experimental set-up. Red lines refer to the incident wave from the transmitter to the sample; green lines represent the reflected wave from the sample to the receiver. The H-grating transmits vertically polarized waves but reflects horizontally polarized waves. The 45D grating selects the E-field components with 45° rotation. (b) Photograph of the transparent absorber consisting of graphene-quartz samples backed with a metal plate.

Mentions: In order to investigate the nanostructured absorber, reflection spectra are measured by a well-established free space millimetre wave reflectometery technique and then transformed to absorption spectra according to equation (8). The experimental set-up is illustrated in Fig. 2a. The reflectometer functions at frequencies from 110 GHz to 170 GHz using a HP N5244A vector network analyzer fitted with millimetre wave extension heads (see Methods section).


Experimental demonstration of a transparent graphene millimetre wave absorber with 28% fractional bandwidth at 140 GHz.

Wu B, Tuncer HM, Naeem M, Yang B, Cole MT, Milne WI, Hao Y - Sci Rep (2014)

Millimetre wave reflectometer measurements.(a) Photograph of the experimental set-up. Red lines refer to the incident wave from the transmitter to the sample; green lines represent the reflected wave from the sample to the receiver. The H-grating transmits vertically polarized waves but reflects horizontally polarized waves. The 45D grating selects the E-field components with 45° rotation. (b) Photograph of the transparent absorber consisting of graphene-quartz samples backed with a metal plate.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3928574&req=5

f2: Millimetre wave reflectometer measurements.(a) Photograph of the experimental set-up. Red lines refer to the incident wave from the transmitter to the sample; green lines represent the reflected wave from the sample to the receiver. The H-grating transmits vertically polarized waves but reflects horizontally polarized waves. The 45D grating selects the E-field components with 45° rotation. (b) Photograph of the transparent absorber consisting of graphene-quartz samples backed with a metal plate.
Mentions: In order to investigate the nanostructured absorber, reflection spectra are measured by a well-established free space millimetre wave reflectometery technique and then transformed to absorption spectra according to equation (8). The experimental set-up is illustrated in Fig. 2a. The reflectometer functions at frequencies from 110 GHz to 170 GHz using a HP N5244A vector network analyzer fitted with millimetre wave extension heads (see Methods section).

Bottom Line: Broadband absorption is a result of mutually coupled Fabry-Perot resonators represented by each graphene-quartz substrate.Millimetre wave reflectometer measurements of the stacked graphene-quartz absorbers demonstrated excellent broadband absorption of 90% with a 28% fractional bandwidth from 125-165 GHz.Our data suggests that the absorbers' operation can also be extended to microwave and low-terahertz bands with negligible loss in performance.

View Article: PubMed Central - PubMed

Affiliation: 1] School of Electronic Engineering and Computer Science, Queen Mary University of London, London, E1 4NS, United Kingdom [2] School of Electronic Engineering, Xidian University, Xi'an, 710071, China.

ABSTRACT
The development of transparent radio-frequency electronics has been limited, until recently, by the lack of suitable materials. Naturally thin and transparent graphene may lead to disruptive innovations in such applications. Here, we realize optically transparent broadband absorbers operating in the millimetre wave regime achieved by stacking graphene bearing quartz substrates on a ground plate. Broadband absorption is a result of mutually coupled Fabry-Perot resonators represented by each graphene-quartz substrate. An analytical model has been developed to predict the absorption performance and the angular dependence of the absorber. Using a repeated transfer-and-etch process, multilayer graphene was processed to control its surface resistivity. Millimetre wave reflectometer measurements of the stacked graphene-quartz absorbers demonstrated excellent broadband absorption of 90% with a 28% fractional bandwidth from 125-165 GHz. Our data suggests that the absorbers' operation can also be extended to microwave and low-terahertz bands with negligible loss in performance.

No MeSH data available.


Related in: MedlinePlus