Scattering{ }¶

Calling sequence

Scattering{ }

Functionality

Specifies the setting for scattering calculation. See Scattering mechanisms for model description.

Dependencies

Depending on ScreeningTemperatureType, Exactly one of TemperatureOffsetParameter, AccuracySelfConsistentElectronTemperature, ElectronTemperatureForScreening must be defined.

Example

Scattering{
    MaterialForScatteringParameters = "well"

    InterfaceRoughness{
        ...
    }

    ThreadingDislocations{
        ...
    }

    AcousticPhononScattering = yes
    AcousticPhononScatteringEnergyMax =

    MonochromaticLOPhonon =
    # TuneLOPhononScattering =  # deprecated
    LOPhononCouplingStrength =
    LOPhononDeformationPotential =

    ScreeningTemperatureType =
    TemperatureOffsetParameter =
    AccuracySelfConsistentElectronTemperature =
    ElectronTemperatureForScreening =
    ImpurityScatteringStrength =

    AlloyScattering = yes
    AlloyScatteringStrength =

    # advanced settings
    SeparateScattering =
    AnharmonicityStrength =
    MinimizeIFRBroadening =

    ElectronElectronScattering =
    HomogeneousCoulomb =
    CoarseGridCoulomb =
    # TuneElectElectScatteringStrength =  # deprecated
    ElectElectScatteringStrength =

    InterfacesCutOff =

    AugerCoefficient =
}

The following keywords are available within this group:

MaterialForScatteringParameters¶

Calling sequence: Scattering{ MaterialForScatteringParameters }
Properties: —
Functionality: —

InterfaceRoughness{ }¶

Calling sequence

Scattering{ InterfaceRoughness{ } }

Properties

usage: \(\mathrm{\textcolor{ForestGreen}{optional\;within\;the\;group}}\)

Functionality

Setting for the interface roughness scattering calculation.

Example

Scattering{
    InterfaceRoughness{
        InterfaceWidth =
        AmplitudeInZ =
        InterfaceAutoCorrelationType =
        CorrelationLengthInXY =
        AxialCorrelationLength =
    }
}

InterfaceRoughness{ InterfaceWidth }¶

Calling sequence

Scattering{ InterfaceRoughness{ InterfaceWidth } }

Properties

type: \(\mathrm{real\;number}\)
values: [0.0, ...)
unit: \(\mathrm{nm}\)

Functionality

—

InterfaceRoughness{ AmplitudeInZ }¶

Calling sequence

Scattering{ InterfaceRoughness{ AmplitudeInZ } }

Properties

type: \(\mathrm{real\;number}\)
values: [0.0, ...)
unit: \(\mathrm{nm}\)

Functionality

—

InterfaceRoughness{ InterfaceAutoCorrelationType }¶

Calling sequence

Scattering{ InterfaceRoughness{ InterfaceAutoCorrelationType } }

Properties

type: \(\mathrm{integer}\)
type: \(\mathrm{character\;string}\)

Functionality

Chooses the type of interface autocorrelation:

0 or exp =

1 or gauss =

2 or hurst =

3 or step =

InterfaceRoughness{ CorrelationLengthInXY }¶

Calling sequence

Scattering{ InterfaceRoughness{ CorrelationLengthInXY } }

Properties

type: \(\mathrm{real\;number}\)
values: [0.0, ...)
unit: \(\mathrm{nm}\)

Functionality

—

InterfaceRoughness{ AxialCorrelationLength }¶

Calling sequence

Scattering{ InterfaceRoughness{ AxialCorrelationLength } }

Properties

type: \(\mathrm{real\;number}\)
values: [0.0, ...)
unit: \(\mathrm{nm}\)

Functionality

—

ThreadingDislocations{ }¶

Calling sequence

Scattering{ ThreadingDislocations{ } }

Properties

usage: \(\mathrm{\textcolor{ForestGreen}{optional\;within\;the\;group}}\)

Functionality

—

Example

Scattering{
    ThreadingDislocations{
        Density =
        FillingFactor =
        TypePNotN =
    }
}

ThreadingDislocations{ Density }¶

Calling sequence

Scattering{ ThreadingDislocations{ Density } }

Properties

type: \(\mathrm{real\;number}\)
values: [0.0, ...)

Functionality

—

ThreadingDislocations{ FillingFactor }¶

Calling sequence

Scattering{ ThreadingDislocations{ FillingFactor } }

Properties

type: \(\mathrm{real\;number}\)
values: [0.0, ...)

Functionality

—

ThreadingDislocations{ TypePNotN }¶

Calling sequence

Scattering{ ThreadingDislocations{ TypePNotN } }

Properties

choices: yes; no
default: no

Functionality

—

AcousticPhononScattering¶

Calling sequence

Scattering{ AcousticPhononScattering }

Properties

choices: yes; no
default: no

Functionality

—

Note

Acoustic phonon scattering is not efficient in general - can be neglected in most cases.

AcousticPhononScatteringEnergyMax¶

Calling sequence

Scattering{ AcousticPhononScatteringEnergyMax }

Properties

type: \(\mathrm{real\;number}\)

Functionality

Sets the maximum acoustic phonon energy.

LOPhononCouplingStrength¶

Calling sequence

Scattering{ LOPhononCouplingStrength }

Properties

type: \(\mathrm{real\;number}\)
values: [0.0, ...)

Functionality

—

LOPhononDeformationPotential¶

Calling sequence

Scattering{ LOPhononDeformationPotential }

Properties

choices: yes; no
default: no

Functionality

—

ScreeningTemperatureType¶

Calling sequence

Scattering{ ScreeningTemperatureType }

Properties

type: \(\mathrm{integer}\)
type: \(\mathrm{character\;string}\)

Functionality

Choose the model for effective temperature of the electrons involved in electrostatic screening. See Charged impurity scattering for the model description.

1 or offset or top =

2 or self =

3 or direct =

TemperatureOffsetParameter¶

Calling sequence

Scattering{ TemperatureOffsetParameter }

Properties

type: \(\mathrm{real\;number}\)
values: [0.0, ...)

Functionality

—

AccuracySelfConsistentElectronTemperature¶

Calling sequence

Scattering{ AccuracySelfConsistentElectronTemperature }

Properties

type: \(\mathrm{real\;number}\)
values: [0.0, ...)

Functionality

—

ElectronTemperatureForScreening¶

Calling sequence

Scattering{ ElectronTemperatureForScreening }

Properties

type: \(\mathrm{real\;number}\)
values: [0.0, ...)

Functionality

—

ImpurityScatteringStrength¶

Calling sequence

Scattering{ ImpurityScatteringStrength }

Properties

type: \(\mathrm{real\;number}\)
default: 1.0

Functionality

Reduce (< 1.0) or enhance (> 1.0) impurity scattering strength to test the impact of this mechanism. It should be 1.0 unless you want to test the influence of impurity scattering.

AlloyScattering¶

Calling sequence

Scattering{ AlloyScattering }

Properties

choices: yes; no
default: no

Functionality

If yes, consider scattering due to alloy disorder. See Alloy scattering for the model description.

AlloyScatteringStrength¶

Calling sequence

Scattering{ AlloyScatteringStrength }

Properties

type: \(\mathrm{real\;number}\)
values: [0.0, ...)

Functionality

—

SeparateScattering¶

Calling sequence

Scattering{ SeparateScattering }

Properties

choices: yes; no
default: no

Functionality

—

MinimizeIFRBroadening¶

Calling sequence

Scattering{ MinimizeIFRBroadening }

Properties

choices: yes; no
default: no

Functionality

—

ElectronElectronScattering¶

Calling sequence

Scattering{ ElectronElectronScattering }

Properties

choices: yes; no
default: no

Functionality

—

HomogeneousCoulomb¶

Calling sequence

Scattering{ HomogeneousCoulomb }

Properties

choices: yes; no
default: no

Functionality

—

CoarseGridCoulomb¶

Calling sequence

Scattering{ CoarseGridCoulomb }

Properties

choices: yes; no
default: yes

Functionality

—

ElectElectScatteringStrength¶

Calling sequence

Scattering{ ElectElectScatteringStrength }

Properties

type: \(\mathrm{real\;number}\)
default: 1.0

Functionality

—

PhononDamping¶

Calling sequence

Scattering{ PhononDamping }

Properties

type: \(\mathrm{real\;number}\)
unit: \(\mathrm{meV}\)

Functionality

Specifies the intrinsic linewidth of transverse optical phonons due to anharmonicity (phonon-phonon scattering). Please see Gain/absorption calculation from NEGF linear response theory for the model description.

Example

Scattering{
    PhononDamping = 2.0
}

InterfacesCutOff¶

Calling sequence

Scattering{ InterfacesCutOff }

Properties

type: \(\mathrm{integer}\)

Functionality

—

AugerCoefficient¶

Calling sequence

Scattering{ AugerCoefficient }

Properties

type: \(\mathrm{real\;number}\)
unit: \(\mathrm{cm^6/s}\)

Functionality

Coefficient of the classical model of Auger recombination rate \(Cnnp\) and \(Cnpp\), where \(n\) and \(p\) are local electron and hole densities, respectively. The \(n\)-type and \(p\)-type Auger coefficients are assumed to be the same (cf. Review paper on interband cascade lasers). Only relevant if NumberOfBands is 8 and valence band states are selected.

Last update: 28/10/2024