scholarly journals Graphene two terminal detector as THz mixer

2021 ◽  
Vol 2086 (1) ◽  
pp. 012054
Author(s):  
A Sh Gazaliev ◽  
M V Moskotin ◽  
V V Belosevich ◽  
M G Rybin ◽  
I A Gayduchenko ◽  
...  
Keyword(s):  
Communication Networks ◽  
Data Transfer ◽  
Single Layer ◽  
Heterodyne Detection ◽  
Single Layer Graphene ◽  
Thz Radiation ◽  
Transfer Rates ◽  
Bowtie Antenna ◽  
Radiation Sources ◽  
Maximum Transmission

Abstract The growing requirements for mobile communication networks (data transfer rates over 100 Gbps) makes it necessary to use carrier signal with a frequency of at least 100 GHz. This requires the development of cheap and broadband sub-terahertz (sub-THz) detectors. Here we report on our recent efforts toward the development of a heterodyne sub-THz detector based on a single layer graphene two-terminal device integrated with a bowtie antenna on a sapphire substrate. Our detector operates at frequency of 140 GHz, which corresponds to the maximum transmission of THz radiation in the Earth’s atmosphere. The heterodyne detection is achieved by quasi-optical coupling of signals from two sub-THz radiation sources to the same detector. The measured frequency bandwidth is 5.8 GHz.

scholarly journals Helium-graphene optical-acoustic converter of extreme ensitivity

2021 ◽  
pp. 78-84
Author(s):  
Igor Gibin ◽  
Peter Kotlyar
Keyword(s):  
Physical Properties ◽  
Single Layer ◽  
High Sensitivity ◽  
Maximum Sensitivity ◽  
Single Layer Graphene ◽  
Thz Radiation ◽  
Layer Graphene ◽  
Technical Solutions ◽  
New Generation ◽  
Graphene Membranes

The prospects for the use of single-layer graphene in the design of optical-acoustic converters (OAC) of a new generation are considered. It is shown that the limiting characteristics of transducers with single-layer graphene membranes can be obtained only in OACs constructed according to the Hayes scheme. The main characteristics of membranes – the main elements of OAC – are considered, and the physical properties of graphene, as the most preferred mate-rial for membranes, are analyzed. Estimates having been made show that the use of SLG gra-phene membranes makes it possible to create IR and THz radiation receivers with cells of the order of tens of microns with extremely high sensitivity. To achieve the maximum sensitivity, it is proposed to perform edge perforation of graphene membranes. A new design scheme of uncooled helium-graphene optoacoustic receivers with theoretically maximum sensitivity and speed and an operating range extended to helium temperatures is proposed. The de-scribed technical solutions can be used as the basis for the design of uncooled.

scholarly journals Dependence of electron transfer dynamics on the number of graphene layers in π-stacked 2D materials: insights from ab initio nonadiabatic molecular dynamics

2019 ◽  
Vol 21 (41) ◽  
pp. 23198-23208 ◽  
Author(s):  
Hamid Mehdipour ◽  
Brendan A. Smith ◽  
Ali T. Rezakhani ◽  
Saeedeh S. Tafreshi ◽  
Nora H. de Leeuw ◽  
...  
Keyword(s):  
Golden Rule ◽  
Single Layer ◽  
Single Layer Graphene ◽  
Fermi Golden Rule ◽  
Time Resolved ◽  
Transfer Rates ◽  
Graphene Layers ◽  
Layer Graphene ◽  
Nonadiabatic Molecular Dynamics ◽  
Rule Order

Time-resolved simulation study has been carried out to explain anti-Fermi Golden rule order of charge transfer rates measured at the interfaces of Zn-phthalocyanine molecule with single-layer graphene and double-layer graphene.

Comparative study of electron transfer on various graphene-metallic contacts

2019 ◽  
Vol 33 (31) ◽  
pp. 1950384
Author(s):  
Di Lu ◽  
Yu-E Yang ◽  
Weichun Zhang ◽  
Caixia Wang ◽  
Jining Fang ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Single Layer ◽  
Annealing Treatment ◽  
Single Layer Graphene ◽  
Strain Effect ◽  
Graphene Surface ◽  
Layer Graphene ◽  
Metallic Contacts ◽  
Nonuniform Strain ◽  
Main Factor

We have investigated Raman spectra of the G and 2D lines of a single-layer graphene (SLG) with metallic contacts. The shift of the G and 2D lines is correlated to two different factors. Before performing annealing treatment or annealing under low temperature, the electron transfer on graphene surface is dominated by nonuniform strain effect. As the annealing treatment is enhanced, however, a suitable annealing treatment can eliminate the nonuniform strain effect where the relative work function (WF) between graphene and metal becomes a main factor to determine electronic transfer. Moreover, it is confirmed that the optimized annealing treatment can also decrease effectively the structural defect and induced disorder in graphene due to metallic contacts.

scholarly journals Millisecond lattice gasification for high-density CO2- and O2-sieving nanopores in single-layer graphene

2021 ◽  
Vol 7 (9) ◽  
pp. eabf0116
Author(s):  
Shiqi Huang ◽  
Shaoxian Li ◽  
Luis Francisco Villalobos ◽  
Mostapha Dakhchoune ◽  
Marina Micari ◽  
...  
Keyword(s):  
Single Layer ◽  
High Density ◽  
Single Layer Graphene ◽  
Pore Density ◽  
Vacancy Defects ◽  
Carbon Gasification ◽  
Layer Graphene ◽  
Gas Molecules ◽  
Good Agreement

Etching single-layer graphene to incorporate a high pore density with sub-angstrom precision in molecular differentiation is critical to realize the promising high-flux separation of similar-sized gas molecules, e.g., CO2 from N2. However, rapid etching kinetics needed to achieve the high pore density is challenging to control for such precision. Here, we report a millisecond carbon gasification chemistry incorporating high density (>1012 cm−2) of functional oxygen clusters that then evolve in CO2-sieving vacancy defects under controlled and predictable gasification conditions. A statistical distribution of nanopore lattice isomers is observed, in good agreement with the theoretical solution to the isomer cataloging problem. The gasification technique is scalable, and a centimeter-scale membrane is demonstrated. Last, molecular cutoff could be adjusted by 0.1 Å by in situ expansion of the vacancy defects in an O2 atmosphere. Large CO2 and O2 permeances (>10,000 and 1000 GPU, respectively) are demonstrated accompanying attractive CO2/N2 and O2/N2 selectivities.

Sign in / Sign up

Export Citation Format

Share Document