Hydrodynamic Simulation of Drift Mobility in N-Hg0.8Cd0.2Te

2011 ◽  
Vol 312-315 ◽  
pp. 122-126
Author(s):  
Mebarka Daoudi ◽  
Abderrahmane Belghachi ◽  
Luca Varani ◽  
Christophe Palermo
Keyword(s):  
Experimental Data ◽  
Electric Field ◽  
Dominant Role ◽  
Impurity Scattering ◽  
Drift Mobility ◽  
Scattering Mechanism ◽  
Hydrodynamic Simulation ◽  
Monte Carlo Calculations ◽  
Ionized Impurity Scattering ◽  
Good Agreement

In this paper, the transport properties of Hg0.8Cd0.2Te have been investigated at 77 K using the hydrodynamic model. We remarked that ionized impurity scattering mechanism plays a dominant role in this material at low electric field. The drift velocity, mean energy and drift mobility are determined as functions of the electric field strength. Comparison is made with Monte Carlo calculations and experimental results. The obtained velocity-field curve is in good agreement with reported experimental data.

Drift mobility and Hall coefficient factor of holes in germanium and silicon

1978 ◽  
Vol 56 (3) ◽  
pp. 364-372 ◽  
Author(s):  
H. Nakagawa ◽  
S. Zukotynski
Keyword(s):  
Experimental Data ◽  
Band Structure ◽  
Hall Coefficient ◽  
Phonon Scattering ◽  
Impurity Scattering ◽  
Drift Mobility ◽  
Structure Model ◽  
Optical Phonon Scattering ◽  
Band Structure Model ◽  
Good Agreement

The drift mobility and the Hall coefficient factor are calculated using the Kane band structure model without approximations. Acoustic and optical phonon scattering and also impurity scattering are considered. The effects of light and heavy holes on the drift and the Hall mobility are discussed. The results for the drift mobility agree with experimental data both for Ge and Si. The results for the Hall coefficient factor are in good agreement for Si, but in the case of Ge, the agreement is only fair.

Electron Mobility In N-Type Epitaxial ZnSe

1990 ◽  
Vol 216 ◽  
Author(s):  
M. Vaziri ◽  
R. Reifenberger
Keyword(s):  
Experimental Data ◽  
Molecular Beam Epitaxy ◽  
Gaas Substrate ◽  
Molecular Beam ◽  
Impurity Scattering ◽  
Poor Agreement ◽  
Temperature Dependent ◽  
Ionized Impurity Scattering ◽  
Data Call ◽  
Good Agreement

ABSTRACTAn analysis of the temperature dependent mobility in lightly doped ZnSe epitaxial layers grown on a semi-insulating GaAs substrate by Molecular Beam Epitaxy is reported. Our results indicate that the temperature dependence of the mobility is in poor agreement with calculated values based on typical phonon and ionized impurity scattering mechanisms. Good agreement between theory and experimental data call be obtained by including a scattering term associated with the space-charge region surrounding defects.

scholarly journals What Determines the Parameters of a Propagating Streamer: A Comparison of Outputs of the Streamer Parameter Model and of Hydrodynamic Simulations

Atmosphere ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1664
Author(s):  
Nikolai G. Lehtinen ◽  
Robert Marskar
Keyword(s):  
Experimental Data ◽  
Electric Field ◽  
Electric Discharge ◽  
Propagation Velocity ◽  
The Novel ◽  
Hydrodynamic Simulation ◽  
Hydrodynamic Simulations ◽  
Important Stage ◽  
Streamer Discharges

Electric streamer discharges (streamers) in the air are a very important stage of lightning, taking place before formation of the leader discharge, and with which an electric discharge starts from conducting objects which enhance the background electric field, such as airplanes. Despite years of research, it is still not well understood what mechanism determines the values of a streamer’s parameters, such as its radius and propagation velocity. The novel Streamer Parameter Model (SPM) was made to explain this mechanism, and to provide a way to efficiently calculate streamer parameters. Previously, we demonstrated that SPM results compared well with a limited set of experimental data. In this article, we compare SPM predictions to the published hydrodynamic simulation (HDS) results.

Mobility of Hot Carriers in Germanium at 300°K

1968 ◽  
Vol 23 (12) ◽  
pp. 2035-2039
Author(s):  
M. Sánchez
Keyword(s):  
Electric Field ◽  
Field Intensity ◽  
Electric Field Intensity ◽  
Average Rate ◽  
Impurity Scattering ◽  
Rate Of Change ◽  
Hot Carriers ◽  
Ionized Impurity Scattering ◽  
Carrier Temperature ◽  
Carrier Energy

The mobility of hot electrons and holes in germanium at a lattice temperature of 300°K is calculated as dependent on carrier temperature and electric field intensity including not only the acoustical and nonpolar optical mode scattering but also the ionized impurity scattering. The Conwell theory of lattice mobility of hot carriers and the Conwell-Weisskopf theory of ionized impurity scattering are applied by taking into account the factor exp (θ/2 Te) in the average rate of change of carrier energy due to nonpolar optical interactions. The mobility is evaluated on an electronic digital computer as a function of the carrier temperature and electric field intensity for impurity concentrations 0, 4 x 1016, 2 x 1017, 1018 and 2.5 x 1019 cm-3, and also as a function of impurity concentration for low electric field intensities. The comparison of the theoretical results with the experimental data available shows a relatively good agreement.

The Effects of the Carrier Concentrations on the Hall Mobilities of ZnO:Al Thin Films Deposited by Magnetron Sputtering

2017 ◽  
Vol 727 ◽  
pp. 938-941
Author(s):  
Xiao Jing Wang ◽  
Yun Zhang
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Magnetron Sputtering ◽  
Carrier Concentration ◽  
Carrier Mobility ◽  
Impurity Scattering ◽  
Flexible Substrates ◽  
Boundary Scattering ◽  
Scattering Mechanism ◽  
Ionized Impurity Scattering

ZnO:Al thin films were deposited on flexible substrates by magnetron sputtering. The effects of the carrier concentrations on the hall mobilities of AZO films were investigated. When the carrier concentration was high (~1020/cm3), the hall mobility decreased with increase of the carrier concentration, showing obvious characteristics of ionized impurity scattering; moreover, the carrier mobility could be expressed to be-2.14/3 proportional of the carrier concentration by combining the results of simulation and experiments.simulation and experiment. When the carrier concentration was about a magnitude of 1019 cm-3, the carrier mobility is influenced by the carrier concentration and grain size, which means the carrier mobility was affected by both the grain boundary scattering and ionized purity scattering mechanism.

scholarly journals Manipulation of ionized impurity scattering for achieving high thermoelectric performance in n-type Mg3Sb2-based materials

2017 ◽  
Vol 114 (40) ◽  
pp. 10548-10553 ◽  
Author(s):  
Jun Mao ◽  
Jing Shuai ◽  
Shaowei Song ◽  
Yixuan Wu ◽  
Rebecca Dally ◽  
...  
Keyword(s):  
Power Factor ◽  
Carrier Mobility ◽  
Phonon Scattering ◽  
Impurity Scattering ◽  
Substantial Improvement ◽  
Thermoelectric Performance ◽  
Scattering Mechanism ◽  
Carrier Scattering ◽  
Ionized Impurity Scattering ◽  
Higher Carrier Mobility

Achieving higher carrier mobility plays a pivotal role for obtaining potentially high thermoelectric performance. In principle, the carrier mobility is governed by the band structure as well as by the carrier scattering mechanism. Here, we demonstrate that by manipulating the carrier scattering mechanism in n-type Mg3Sb2-based materials, a substantial improvement in carrier mobility, and hence the power factor, can be achieved. In this work, Fe, Co, Hf, and Ta are doped on the Mg site of Mg3.2Sb1.5Bi0.49Te0.01, where the ionized impurity scattering crosses over to mixed ionized impurity and acoustic phonon scattering. A significant improvement in Hall mobility from ∼16 to ∼81 cm2⋅V−1⋅s−1 is obtained, thus leading to a notably enhanced power factor of ∼13 μW⋅cm−1⋅K−2 from ∼5 μW⋅cm−1⋅K−2. A simultaneous reduction in thermal conductivity is also achieved. Collectively, a figure of merit (ZT) of ∼1.7 is obtained at 773 K in Mg3.1Co0.1Sb1.5Bi0.49Te0.01. The concept of manipulating the carrier scattering mechanism to improve the mobility should also be applicable to other material systems.

HALL MOBILITY IN n-TYPE 4H-SiC: CALCULATION USING HYDRODYNAMIC BALANCE EQUATIONS

2002 ◽  
Vol 16 (03) ◽  
pp. 463-471 ◽  
Author(s):  
HONG-JUN QUAN ◽  
BING-HONG WANG ◽  
XIAO-SHU LUO
Keyword(s):  
Experimental Data ◽  
High Temperature ◽  
Hall Mobility ◽  
Optical Lattice ◽  
Significant Contribution ◽  
Impurity Scattering ◽  
Temperature Data ◽  
Balance Equations ◽  
Neutral Impurity ◽  
Good Agreement

The Hall mobility in n-type 4H-SiC has been calculated by hydrodynamic balance equations for temperatures ranging from 30 to 1000 K. We employ a compensation model to analyze the carrier concentration versus temperature data. The results show that the neutral impurity scattering and the piezoelectric scattering do not make significant contribution to the electron mobility. The low-temperature value of the mobility is mainly due to the ionized impurity while the high-temperature tail is limited by acoustic, polar optical and intervalley optical lattice scatterings. These results are in good agreement with the experimental data.

scholarly journals Evidence of Intersubband Linewidth Narrowing Using Growth Interruption Technique

Photonics ◽  
2019 ◽  
Vol 6 (2) ◽  
pp. 38 ◽  
Author(s):  
Ngoc Tran ◽  
Giorgio Biasiol ◽  
Arnaud Jollivet ◽  
Alberto Bertocci ◽  
François Julien ◽  
...  
Keyword(s):  
Impurity Scattering ◽  
Undoped Sample ◽  
Interface Roughness ◽  
Threshold Intensity ◽  
Scattering Mechanism ◽  
Intersubband Transitions ◽  
Growth Interruption ◽  
Ionized Impurity Scattering ◽  
Interface Roughness Scattering ◽  
Coherent Emission

We report on the systematic study of two main scattering mechanisms on intersubband transitions, namely ionized impurity scattering and interface roughness scattering. The former mechanism has been investigated as a function of the dopants position within a multiple GaAs/AlGaAs quantum well structure and compared to the transition of an undoped sample. The study on the latter scattering mechanism has been conducted using the growth interruption technique. We report an improvement of the intersubband (ISB) transition linewidth up to 11% by interrupting growth at GaAs-on-AlGaAs interfaces. As a result, the lifetime of intersubband polaritons could be improved up to 9%. This leads to a reduction of 17% of the theoretical threshold intensity for polaritonic coherent emission. This work brings a useful contribution towards the realization of polariton-based devices.

scholarly journals Analytical model for electrohydrodynamic thrust

2020 ◽  
Vol 476 (2241) ◽  
pp. 20200220
Author(s):  
Ravi Sankar Vaddi ◽  
Yifei Guan ◽  
Alexander Mamishev ◽  
Igor Novosselov
Keyword(s):  
Experimental Data ◽  
Electric Field ◽  
Momentum Transfer ◽  
Analytical Model ◽  
First Principles ◽  
Thrust Force ◽  
Propulsion Systems ◽  
One Dimensional ◽  
Charged Species ◽  
Good Agreement

Electrohydrodynamic (EHD) thrust is produced when ionized fluid is accelerated in an electric field due to the momentum transfer between the charged species and neutral molecules. We extend the previously reported analytical model that couples space charge, electric field and momentum transfer to derive thrust force in one-dimensional planar coordinates. The electric current density in the model can be expressed in the form of Mott–Gurney law. After the correction for the drag force, the EHD thrust model yields good agreement with the experimental data from several independent studies. The EHD thrust expression derived from the first principles can be used in the design of propulsion systems and can be readily implemented in the numerical simulations.

Interpretation of High Field Transport in A-Si:H Based on the Effective Temperature Definition

1994 ◽  
Vol 336 ◽  
Author(s):  
Christoph E. Nebel ◽  
R. A. Street
Keyword(s):  
Electric Field ◽  
Effective Temperature ◽  
High Field ◽  
Dark Conductivity ◽  
Drift Mobility ◽  
Mobility Data ◽  
Wide Range ◽  
Temperature Concept ◽  
Temperature Definition ◽  
Good Agreement

ABSTRACTThe effective temperature definition which combines electric field and lattice temperature is critically discussed based on dark conductivity and drift mobility data measured over a wide range of temperature (10 K ≤ T ≤ 300 K) and electric field (102 V/cm ≤ F ≤ 6×105 V/cm). The reasonable values for the localisation lengths of electrons (αe ≡ 7–8 A) and holes (αh, ≡ 4 A) as well as the overall good agreement between predicted and deduced features support the effective temperature concept. A statistical transit time equation for transport at low temperature and high field is given and discussed based on time-of-flight data measured at T = 40 K.

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