Low-Bias Active Control of Terahertz Waves by Coupling Large-Area CVD Graphene to a Terahertz Metamaterial

Nano Letters ◽  
2013 ◽  
Vol 13 (7) ◽  
pp. 3193-3198 ◽  
Author(s):  
Federico Valmorra ◽  
Giacomo Scalari ◽  
Curdin Maissen ◽  
Wangyang Fu ◽  
Christian Schönenberger ◽  
...  
Keyword(s):  
Active Control ◽  
Terahertz Waves ◽  
Large Area ◽  
Cvd Graphene

Exploring and rationalising effective n-doping of large area CVD-graphene by NH3

2014 ◽  
Vol 16 (8) ◽  
pp. 3632 ◽  
Author(s):  
G. V. Bianco ◽  
M. Losurdo ◽  
M. M. Giangregorio ◽  
P. Capezzuto ◽  
G. Bruno
Keyword(s):  
Large Area ◽  
Cvd Graphene ◽  
N Doping

scholarly journals Terahertz Beam Steering Concept Based on a MEMS-Reconfigurable Reflection Grating

Sensors ◽  
2020 ◽  
Vol 20 (10) ◽  
pp. 2874
Author(s):  
Xuan Liu ◽  
Lisa Samfaß ◽  
Kevin Kolpatzeck ◽  
Lars Häring ◽  
Jan C. Balzer ◽  
...  
Keyword(s):  
Diffraction Grating ◽  
High Speed ◽  
Beam Steering ◽  
Vertical Displacement ◽  
Grating Period ◽  
Terahertz Waves ◽  
Large Area ◽  
Electrostatic Actuators ◽  
Reflection Gratings ◽  
Reflection Grating

With an increasing number of applications of terahertz systems in industrial fields and communications, terahertz beamforming and beam steering techniques are required for high-speed, large-area scanning. As a promising means for beam steering, micro-electro-mechanical system (MEMS)-based reflection gratings have been successfully implemented for terahertz beam control. So far, the diffraction grating efficiency is relatively low due to the limited vertical displacement range of the reflectors. In this paper, we propose a design for a reconfigurable MEMS-based reflection grating consisting of multiple subwavelength reflectors which are driven by 5-bit, high-throw electrostatic actuators. We vary the number of the reflectors per grating period and configure the throw of individual reflectors so that the reflection grating is shaped as a blazed grating to steer the terahertz beam with maximum diffraction grating efficiency. Furthermore, we provide a mathematical model for calculating the radiation pattern of the terahertz wave reflected by general reflection gratings consisting of subwavelength reflectors. The calculated and simulated radiation patterns of the designed grating show that we can steer the angle of the terahertz waves in a range of up to ± 56.4 ∘ with a maximum sidelobe level of −10 dB at frequencies from 0.3 THz to 1 THz.

scholarly journals Microwave absorption and radiation from large-area multilayer CVD graphene

Carbon ◽  
2014 ◽  
Vol 77 ◽  
pp. 814-822 ◽  
Author(s):  
Bian Wu ◽  
Hatice M. Tuncer ◽  
Anestis Katsounaros ◽  
Weiping Wu ◽  
Matthew T. Cole ◽  
...  
Keyword(s):  
Microwave Absorption ◽  
Large Area ◽  
Cvd Graphene

scholarly journals Perovskite Solar Cells with Large-Area CVD-Graphene for Tandem Solar Cells

2015 ◽  
Vol 6 (14) ◽  
pp. 2745-2750 ◽  
Author(s):  
Felix Lang ◽  
Marc A. Gluba ◽  
Steve Albrecht ◽  
Jörg Rappich ◽  
Lars Korte ◽  
...  
Keyword(s):  
Solar Cells ◽  
Perovskite Solar Cells ◽  
Large Area ◽  
Tandem Solar Cells ◽  
Cvd Graphene

Adlayer-free large-area single-crystal CVD graphene growth on copper

2020 ◽  
Vol 31 (24) ◽  
pp. 21821-21831
Author(s):  
Chaitanya Arya ◽  
K. Kanishka H. De Silva ◽  
Masamichi Yoshimura
Keyword(s):  
Single Crystal ◽  
Large Area ◽  
Graphene Growth ◽  
Cvd Graphene

Metamaterials for Enhanced Optical Responses and their Application to Active Control of Terahertz Waves

2020 ◽  
Vol 32 (35) ◽  
pp. 2000250
Author(s):  
Seojoo Lee ◽  
Soojeong Baek ◽  
Teun‐Teun Kim ◽  
Hyukjoon Cho ◽  
Sangha Lee ◽  
...  
Keyword(s):  
Active Control ◽  
Terahertz Waves ◽  
Optical Responses

Functionalization of any substrate using covalently modified large area CVD graphene

2017 ◽  
Vol 53 (67) ◽  
pp. 9308-9311 ◽  
Author(s):  
Felix Rösicke ◽  
Marc A. Gluba ◽  
Timur Shaykhutdinov ◽  
Guoguang Sun ◽  
Christoph Kratz ◽  
...  
Keyword(s):  
Functionalized Graphene ◽  
Large Area ◽  
Cvd Graphene

The transfer of p-(N-maleimido)phenyl functionalized graphene has been shown to be robust and lossless.

scholarly journals Correlation of p-doping in CVD Graphene with Substrate Surface Charges

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
S. Goniszewski ◽  
M. Adabi ◽  
O. Shaforost ◽  
S. M. Hanham ◽  
L. Hao ◽  
...  
Keyword(s):  
Contact Angle ◽  
Gate Voltage ◽  
Dirac Point ◽  
Substrate Surface ◽  
Chemical Vapour ◽  
Charge Carrier Density ◽  
Surface Charges ◽  
Large Area ◽  
Cvd Graphene ◽  
Graphene Field Effect Transistor

Abstract Correlations between the level of p-doping exhibited in large area chemical vapour deposition (CVD) graphene field effect transistor structures (gFETs) and residual charges created by a variety of surface treatments to the silicon dioxide (SiO2) substrates prior to CVD graphene transfer are measured. Beginning with graphene on untreated thermal oxidised silicon, a minimum conductivity (σ min ) occurring at gate voltage V g  = 15 V (Dirac Point) is measured. It was found that more aggressive treatments (O2 plasma and UV Ozone treatments) further increase the gate voltage of the Dirac point up to 65 V, corresponding to a significant increase of the level of p-doping displayed in the graphene. An electrowetting model describing the measured relationship between the contact angle (θ) of a water droplet applied to the treated substrate/graphene surface and an effective gate voltage from a surface charge density is proposed to describe biasing of V g at σ min and was found to fit the measurements with multiplication of a correction factor, allowing effective non-destructive approximation of substrate added charge carrier density using contact angle measurements.

Sign in / Sign up

Export Citation Format

Share Document