DRIFT VELOCITY AND MOBILITY OF A GRAPHENE NANORIBBON IN A HIGH MAGNITUDE ELECTRIC FIELD

2011 ◽  
Author(s):  
N. A. Amin ◽  
M. T. Ahmadi ◽  
Z. Johari ◽  
J. F. Webb ◽  
S. M. Mousavi ◽  
...  
Keyword(s):  
Electric Field ◽  
Drift Velocity ◽  
Graphene Nanoribbon ◽  
High Magnitude

Electron drift velocity versus electric field in GaAs

1986 ◽  
Vol 29 (12) ◽  
pp. 1295-1296 ◽  
Author(s):  
Chian S. Chang ◽  
Harold R. Fetterman
Keyword(s):  
Electric Field ◽  
Drift Velocity ◽  
Electron Drift Velocity ◽  
Velocity Versus ◽  
Electron Drift

EDGE MAGNETISM AND QUANTUM SPIN HALL EFFECT IN ZIGZAG GRAPHENE NANORIBBON

2013 ◽  
Vol 27 (15) ◽  
pp. 1362011 ◽  
Author(s):  
JUN-WON RHIM ◽  
KYUNGSUN MOON
Keyword(s):  
Electric Field ◽  
Hall Effect ◽  
Graphene Nanoribbon ◽  
Quantum Spin ◽  
Spin Hall Effect ◽  
Nonmonotonic Dependence ◽  
Quantum Spin Hall Effect ◽  
Edge Spin ◽  
Edge Band ◽  
Quantum Spin Hall

We present here a brief review on the remarkable consequences of the flat bands formed at the edges of the Zigzag graphene nanoribbon (ZGNR). The inclusion of the on-site Coulomb interaction is shown to induce the edge spin ferromagnetism, whose spin stiffness demonstrates a nonmonotonic dependence on the lateral electric field. The critical electric field strength corresponds to that of the insulator to half-metal transition. The inclusion of the spin–orbit coupling (SOC) has been believed to generate the quantum spin Hall effect (QSHE) guiding into the interesting new field of topological insulator. By carefully investigating the SOC near the edge, we have shown that the additional σ-edge band gives a marginal perturbation and hence the existence of the QSHE depends on the coupling strength between the π-edge bands and the σ-edge band. We demonstrate that for the charge neutral ZGNR, the QSHE does not occur in the pristine ZGNR, while the hydrogen passivation along the edge may recover the expected feature of the QSHE.

Planar rotation of electric field induced by edge-plasmon in a graphene nanoribbon

2019 ◽  
Vol 100 (15) ◽  
Author(s):  
M. Shoufie Ukhtary ◽  
Masato Maruoka ◽  
Riichiro Saito
Keyword(s):  
Electric Field ◽  
Graphene Nanoribbon ◽  
Planar Rotation

scholarly journals Mechanisms of the electron density depletion in the SAR arc region

1996 ◽  
Vol 14 (2) ◽  
pp. 211-221 ◽  
Author(s):  
A. V. Pavlov
Keyword(s):  
Electric Field ◽  
Magnetic Storm ◽  
Electron Density ◽  
Drift Velocity ◽  
Recovery Phase ◽  
Electron Densities ◽  
Model Framework ◽  
Vibrationally Excited ◽  
Plasma Drift ◽  
Excited Nitrogen

Abstract. This study compares the measurements of electron density and temperature and the integral airglow intensity at 630 nm in the SAR arc region and slightly south of this (obtained by the Isis 2 spacecraft during the 18 December 1971 magnetic storm), with the model results obtained using the time dependent one-dimensional mathematical model of the Earth\\'s ionosphere and plasmasphere. The explicit expression in the third Enskog approximation for the electron thermal conductivity coefficient in the multicomponent mixture of ionized gases and a simplified calculation method for this coefficient presents an opportunity to calculate more exactly the electron temperature and density and 630 nm emission within SAR arc region are used in the model. Collisions between N2 and hot thermal electrons in the SAR arc region produce vibrationally excited nitrogen molecules. It appears that the loss rate of O+(4S) due to reactions with the vibrationally excited nitrogen is enough to explain electron density depression by a factor of two at F-region heights and the topside ionosphere density variations within the SAR arc if the erosion of plasma within geomagnetic field tubes, during the main phase of the geomagnetic storm and subsequent filling of geomagnetic tubes during the recovery phase, are considered. To explain the disagreement by a factor 1.5 between the observed and modeled SAR arc electron densities an additional plasma drift velocity ~–30 m s–1 in the ion continuity equations is needed during the recovery phase. This additional plasma drift velocity is likely caused by the transition from convecting to corotating flux tubes on the equatorward wall of the trough. The electron densities and temperatures and 630 nm integral intensity at the SAR arc and slightly south of this region as measured for the 18 December 1971 magnetic storm were correctly described by the model without perpendicular electric fields. Within this model framework the effect of the perpendicular electric field ~100 mv m–1 with a duration ~1 h on the SAR arc electron density profiles was found to be large. However, this effect is small if ~1–2 h have passed after the electric field was set equal to zero.

scholarly journals Drift Velocity, Longitudinal and Transverse Diffusion in Hydrocarbons derived from Distributions of Single Electrons

1992 ◽  
Vol 45 (3) ◽  
pp. 351 ◽  
Author(s):  
Bernhard Schmidt ◽  
Michael Roncossek
Keyword(s):  
Field Strength ◽  
Electric Field ◽  
Electric Field Strength ◽  
Drift Velocity ◽  
Simultaneous Measurement ◽  
Diffusion Coefficients ◽  
Number Density ◽  
Transverse Diffusion ◽  
Single Electrons ◽  
Time Of Flight Method

A time of flight method is described which allows the simultaneous measurement of drift velocity w and the ratios of the longitudinal and transverse diffusion coefficients to mobility (DL/JL, DT/JL) of electrons in gases. The accuracy achieved in this omnipurpose experiment is comparable with that of specialised techniques and is estimated to be �1 % for w and �5% for the D / JL measurements .. Results for methane, ethane, ethene, propane, propene and cyclopropane for values of E/N (the electric field strength divided by the number density) ranging from 0�02 to 15 Td are presented and discussed (1 Td = 10-21 Vm2 ).

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