Modeling the Charge Transport in Graphene Nano Ribbon Interfaces for Nano Scale Electronic Devices

Ravinder Kumar; Derick Engles

doi:10.1142/s1756973714500036

Modeling the Charge Transport in Graphene Nano Ribbon Interfaces for Nano Scale Electronic Devices

Journal of Multiscale Modelling ◽

10.1142/s1756973714500036 ◽

2015 ◽

Vol 06 (01) ◽

pp. 1450003

Author(s):

Ravinder Kumar ◽

Derick Engles

Keyword(s):

Charge Transport ◽

Electronic Devices ◽

Research Work ◽

Channel Length ◽

Electronic Charge ◽

Transport Parameters ◽

Nano Scale ◽

Metal Semiconductor Metal ◽

Semi Empirical ◽

Non Equilibrium

In this research work we have modeled, simulated and compared the electronic charge transport for Metal-Semiconductor-Metal interfaces of Graphene Nano Ribbons (GNR) with different geometries using First-Principle calculations and Non-Equilibrium Green's Function (NEGF) method. We modeled junctions of Armchair GNR strip sandwiched between two Zigzag strips with (Z-A-Z) and Zigzag GNR strip sandwiched between two Armchair strips with (A-Z-A) using semi-empirical Extended Huckle Theory (EHT) within the framework of Non-Equilibrium Green Function (NEGF). I-V characteristics of the interfaces were visualized for various transport parameters. The distinct changes in conductance and I-V curves reported as the Width across layers, Channel length (Central part) was varied at different bias voltages from -1V to 1 V with steps of 0.25 V. From the simulated results we observed that the conductance through A-Z-A graphene junction is in the range of 10-13 Siemens whereas the conductance through Z-A-Z graphene junction is in the range of 10-5 Siemens. These suggested conductance controlled mechanisms for the charge transport in the graphene interfaces with different geometries is important for the design of graphene based nano scale electronic devices like Graphene FETs, Sensors.

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Effect of Metallic Electrodes Ensemble on Charge Transport Characteristics of Cytosine Based Molecular Devices

Journal of Nanoelectronics and Optoelectronics ◽

10.1166/jno.2019.2646 ◽

2019 ◽

Vol 14 (11) ◽

pp. 1589-1596 ◽

Cited By ~ 1

Author(s):

Rajan Vohra ◽

Ravinder Singh Sawhney

Keyword(s):

Charge Transport ◽

Transport Properties ◽

Electrode Materials ◽

Molecular Devices ◽

Molecular Device ◽

Transport Parameters ◽

Hückel Theory ◽

Silver Electrodes ◽

Homo Lumo ◽

Non Equilibrium

The charge transport through molecular devices using an ensemble of metal electrodes having nucleobase cytosine as the central molecule has been envisaged using a combination of semi-empirical Extended Huckel Theory and Non Equilibrium Green Function (NEGF). FFT-2D computational approach has been effectively applied to elucidate the electron transport characteristics of these molecular devices under both equilibrium as well as non-equilibrium states. The charge transport parameters viz. Device Density of States, Transmission Spectrum, I–V curve, G–V curve and HOMO-LUMO Gap are measured to exhibit the charge transport properties. By comparing the obtained quantum transport properties, we observe that silver remains the best choice among the three electrode materials under study as the molecular device with the silver electrodes exhibits the lower HOMO-LUMO Gap with increased current and conductance for the higher bias voltages in contrast to the other two configurations which show comparatively higher value of HOMO-LUMO Gap. Hence, the molecular device with the silver electrodes has greater possibility of getting utilized as a switch in DNA based nano-electronics applications.

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Proliferating conduction by isomerism

International Journal of Computational Materials Science and Engineering ◽

10.1142/s2047684115500244 ◽

2015 ◽

Vol 04 (04) ◽

pp. 1550024 ◽

Cited By ~ 1

Author(s):

Rupan Preet Kaur ◽

Ravinder Singh Sawhney ◽

Derick Engles

Keyword(s):

Electron Transport ◽

Electrical Conduction ◽

Empirical Model ◽

Research Work ◽

Gold Electrodes ◽

Transport Parameters ◽

Hückel Theory ◽

Anthracene Molecule ◽

Semi Empirical ◽

Maximum Conductance

The electrical conduction of isomers of anthracene molecule attached between two semi-infinite gold electrodes was simulated using extended Huckel theory (EHT)-based on semi-empirical model in this research work. The electron transport parameters were examined in two epochs by buffering anthracene and its isomer phenanthrene alternatively between gold electrodes using sulphur as an alligator clip, under variegated bias voltages. Differential NDR effect was observed in both the cases but phenanthrene exhibited more linear I–V curve than its counterpart, anthracene. The simulated results discovered phenanthrene as a better candidate than anthracene towards contributing to electrical conduction in molecular junctions. Phenanthrene reported maximum conductance of 0.74G0 whereas anthracene exhibited 0.03[Formula: see text]G0 at 0.8[Formula: see text]V.

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Ultrahigh-Vacuum Electron Microscopy for Gold Nanostructures

Microscopy and Microanalysis ◽

10.1017/s1431927600030671 ◽

2001 ◽

Vol 7 (S2) ◽

pp. 920-921

Author(s):

Yukihito Kondo ◽

Kimiharu Okamoto ◽

Mikio Naruse ◽

Toshikazu Honda ◽

Mike Kersker

Keyword(s):

Electron Microscopy ◽

Field Emission ◽

Electronic Devices ◽

Ultrahigh Vacuum ◽

Gold Nanostructures ◽

Scanning Tunneling ◽

Nano Scale ◽

Transmission Electron ◽

Column Type ◽

Schottky Type

Ultrahigh-vacuum transmission electron microscopy (UHVTEM) has become increasingly popular for the direct observation of nanostructures having clean surfaces, since industrial requirements to make and research nano-scale materials have been rapidly growing for quantum or nanoscale electronic devices. Since we have first developed high resolution UHVTEM in 1986, the UHVTEMs have been evolved with steady advances such as UHV compatible goniometer, field emission gun or etc. Furthermore, the UHVTEM started to combine analytical capabilities such as energy dispersive X-ray spectrometer, in-column type energy filter and etc., and to combine STM (scanning tunneling microscope). The UHV technology is essential for the analysis, because the portion of contaminant in a nano-scale specimen increases as the size of the specimen goes down. This paper reports the results of gold nanostructures by recently the developed UHVTEM.Figure 1 shows recently developed UHVTEM with Schottky type field emission gun.

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Monolayer Twisted Graphene-Based Schottky Transistor

Materials ◽

10.3390/ma14154109 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4109

Author(s):

Ramin Ahmadi ◽

Mohammad Taghi Ahmadi ◽

Seyed Saeid Rahimian Koloor ◽

Michal Petrů

Keyword(s):

Dispersion Relation ◽

Quantum Tunneling ◽

Research Study ◽

Channel Length ◽

New Class ◽

Metal Semiconductor Metal ◽

The Relationship ◽

Graphene Structures ◽

Twisted Graphene ◽

Device Technology

The outstanding properties of graphene-based components, such as twisted graphene, motivates nanoelectronic researchers to focus on their applications in device technology. Twisted graphene as a new class of graphene structures is investigated in the platform of transistor application in this research study. Therefore, its geometry effect on Schottky transistor operation is analyzed and the relationship between the diameter of twist and number of twists are explored. A metal–semiconductor–metal twisted graphene-based junction as a Schottky transistor is considered. By employing the dispersion relation and quantum tunneling the variation of transistor performance under channel length, the diameter of twisted graphene, and the number of twists deviation are studied. The results show that twisted graphene with a smaller diameter affects the efficiency of twisted graphene-based Schottky transistors. Additionally, as another main characteristic, the ID-VGS is explored, which indicates that the threshold voltage is increased by diameter and number of twists in this type of transistor.

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Nano-scale observation of charge transport and potential distribution of photovoltaic Cu(In,Ga)Se2 thin-films

2011 IEEE Nanotechnology Materials and Devices Conference ◽

10.1109/nmdc.2011.6155335 ◽

2011 ◽

Author(s):

A. R. Jeong ◽

W. Jo ◽

H. J. Jo ◽

D.-H. Kim ◽

S. J. Sung ◽

...

Keyword(s):

Thin Films ◽

Charge Transport ◽

Potential Distribution ◽

Nano Scale

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Conformations and charge transport characteristics of biphenyldithiol self-assembled-monolayer molecular electronic devices: A multiscale computational study

The Journal of Chemical Physics ◽

10.1063/1.1937391 ◽

2005 ◽

Vol 122 (24) ◽

pp. 244703 ◽

Cited By ~ 35

Author(s):

Yong-Hoon Kim ◽

Seung Soon Jang ◽

William A. Goddard

Keyword(s):

Charge Transport ◽

Computational Study ◽

Electronic Devices ◽

Molecular Electronic ◽

Self Assembled Monolayer ◽

Self Assembled ◽

Molecular Electronic Devices

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Electronic Charge Transport Phenomena Directed Smart Fabrication of Metal-Semiconductor Based Electronic Junction Device by A Supramolecular Mn(II)-Metallogel

Journal of Molecular Liquids ◽

10.1016/j.molliq.2021.116769 ◽

2021 ◽

pp. 116769

Author(s):

Santanu Majumdar ◽

Sayantan Sil ◽

Rajib Sahu ◽

Madhuri Ghosh ◽

Gerald Lepcha ◽

...

Keyword(s):

Charge Transport ◽

Transport Phenomena ◽

Electronic Charge ◽

Junction Device

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Polymorphism and the influence of crystal structure on the luminescence of the opto-electronic material 4,4′-bis(9-carbazolyl)biphenyl

CrystEngComm ◽

10.1039/c4ce01056f ◽

2014 ◽

Vol 16 (33) ◽

pp. 7621-7625 ◽

Cited By ~ 10

Author(s):

Cody J. Gleason ◽

Jordan M. Cox ◽

Ian M. Walton ◽

Jason B. Benedict

Keyword(s):

Crystal Structure ◽

Electronic Structure ◽

Electronic Material ◽

Single Crystal ◽

Charge Transport ◽

Luminescent Properties ◽

Electronic Structure Calculations ◽

Electronic Charge ◽

Single Crystal Structures ◽

Structure Calculations

Single crystal structures, luminescent properties and electronic structure calculations of three polymorphs of the opto-electronic charge transport material 4,4′-bis(9-carbazolyl)biphenyl.

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