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lammps/lib/atc/ElectronFlux.h
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ElectronFlux.h
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#ifndef ELECTRON_FLUX_H
#define ELECTRON_FLUX_H
#include <map>
#include <string>
#include "ATC_TypeDefs.h"
namespace ATC {
/**
* @class ElectronFlux
* @brief Base class for the flux appearing in the electron density transport equation
*/
class ElectronFlux
{
public:
ElectronFlux();
virtual ~ElectronFlux() {};
/** computes flux */
virtual void electron_flux(const FIELD_MATS &fields,
const GRAD_FIELD_MATS &gradFields,
DENS_MAT_VEC &flux)
{
FIELD_MATS::const_iterator etField = fields.find(ELECTRON_TEMPERATURE);
const DENS_MAT & etMat = etField->second;
zeroWorkspace_.reset(etMat.nRows(),etMat.nCols());
flux[0] = zeroWorkspace_;
flux[1] = zeroWorkspace_;
flux[2] = zeroWorkspace_;
};
void electron_convection(const FIELD_MATS &fields,
DENS_MAT_VEC &flux)
{
FIELD_MATS::const_iterator edField = fields.find(ELECTRON_DENSITY);
FIELD_MATS::const_iterator evField = fields.find(ELECTRON_VELOCITY);
const DENS_MAT & n = edField->second;
const DENS_MAT & v = evField->second;
const CLON_VEC vx(v,CLONE_COL,0);
const CLON_VEC vy(v,CLONE_COL,1);
const CLON_VEC vz(v,CLONE_COL,2);
zeroWorkspace_.reset(v.nRows(),1);
if (maskX_) {
flux[0] = zeroWorkspace_;
}
else {
flux[0] = vx;
flux[0] *= n; // scale by n
}
if (maskY_) {
flux[1] = zeroWorkspace_;
}
else {
flux[1] = vy;
flux[1] *= n;
}
if (maskZ_) {
flux[2] = zeroWorkspace_;
}
else {
flux[2] = vz;
flux[2] *= n;
}
};
protected:
bool maskX_, maskY_, maskZ_;
DENS_MAT zeroWorkspace_;
};
//-----------------------------------------------------------------------
/**
* @class ElectronFluxLinear
* @brief Class for drift-diffusion electron flux with linear dependency on the electron density gradient
*/
class ElectronFluxLinear : public ElectronFlux
{
public:
ElectronFluxLinear(std::fstream &matfile, std::map<std::string,double> & parameters);
virtual ~ElectronFluxLinear() {};
virtual void electron_flux(const FIELD_MATS &fields,
const GRAD_FIELD_MATS &gradFields,
DENS_MAT_VEC &flux)
{
FIELD_MATS::const_iterator edField = fields.find(ELECTRON_DENSITY);
GRAD_FIELD_MATS::const_iterator dEdField = gradFields.find(ELECTRON_DENSITY);
GRAD_FIELD_MATS::const_iterator dPhiField = gradFields.find(ELECTRIC_POTENTIAL);
// J_n = - \mu n E - D grad n
// note electrons move counter to electric field grad E = - grad \phi
const DENS_MAT & n = edField->second;
const DENS_MAT_VEC & dn = dEdField->second;
const DENS_MAT_VEC & dphi = dPhiField->second;
//n.print("DENSITY");
//for (int i = 0; i < 3; i++) {
// dn[i].print("GRAD N");
// dphi[i].print("GRAD PHI");
//}
//cout << "------------------------------------------------====\n";
flux[0] = n;
flux[1] = n;
flux[2] = n;
if (maskX_)
flux[0] = 0.;
else {
flux[0] *= electronMobility_*dphi[0]; // scale by n to get : n \mu grad(\phi)
flux[0] += -electronDiffusivity_* dn[0];
}
if (maskY_)
flux[1] = 0.;
else {
flux[1] *= electronMobility_* dphi[1] ;
flux[1] += -electronDiffusivity_* dn[1];
}
if (maskZ_)
flux[2] = 0.;
else {
flux[2] *= electronMobility_*dphi[2];
flux[2] += -electronDiffusivity_* dn[2];
}
};
protected:
double electronMobility_, electronDiffusivity_;
};
//-----------------------------------------------------------------------
/**
* @class ElectronFluxThermopower
* @brief Class for defining the electron flux (i.e., current) to include the elctron velocity or have a electron temperature-dependent mobility
*/
class ElectronFluxThermopower : public ElectronFlux
{
public:
ElectronFluxThermopower(std::fstream &matfile,std::map<std::string,double> & parameters);
virtual ~ElectronFluxThermopower() {};
virtual void electron_flux(const FIELD_MATS &fields,
const GRAD_FIELD_MATS &gradFields,
DENS_MAT_VEC &flux)
{
if (fields.find(ELECTRON_VELOCITY)!=fields.end()) {
// J_n = - e n v, note the electron charge e is unity
electron_convection(fields,flux);
flux[0] *= -1;
flux[1] *= -1;
flux[2] *= -1;
}
else {
FIELD_MATS::const_iterator edField = fields.find(ELECTRON_DENSITY);
FIELD_MATS::const_iterator etField = fields.find(ELECTRON_TEMPERATURE);
GRAD_FIELD_MATS::const_iterator dEdField = gradFields.find(ELECTRON_VELOCITY);
GRAD_FIELD_MATS::const_iterator dPhiField = gradFields.find(ELECTRIC_POTENTIAL);
GRAD_FIELD_MATS::const_iterator dEtField = gradFields.find(ELECTRON_TEMPERATURE);
// J_n = - \mu n grad \phi - \mu kB/e T_e grad n
// - \mu S n grad T_e - \mu kB/e n grad T_e
const DENS_MAT & n = edField->second;
const DENS_MAT_VEC & dn = dEdField->second;
const DENS_MAT_VEC & dphi = dPhiField->second;
const DENS_MAT_VEC & dT = dEtField->second;
flux[0] = -electronMobility_*dphi[0];
flux[1] = -electronMobility_*dphi[1];
flux[2] = -electronMobility_*dphi[2];
double coef = -electronMobility_*(seebeckCoef_ + kBeV_);
flux[0] += coef* dT[0];
flux[1] += coef* dT[1];
flux[2] += coef* dT[2];
flux[0] *= n; // scale by n
flux[1] *= n;
flux[2] *= n;
//GRAD_FIELD tmp = dn;
const DENS_MAT & Te = etField->second;
//tmp[0] *= Te;
//tmp[1] *= Te;
//tmp[2] *= Te;
coef = -electronMobility_*kBeV_;
//flux[0] += tmp[0];
flux[0] += dn[0].mult_by_element(Te);
flux[1] += dn[1].mult_by_element(Te);
flux[2] += dn[2].mult_by_element(Te);
}
};
protected:
double electronMobility_, seebeckCoef_;
};
//-----------------------------------------------------------------------
/**
* @class ElectronFluxConvection
* @brief Class for electron flux based on the standard convection term
*/
class ElectronFluxConvection : public ElectronFlux
{
public:
ElectronFluxConvection(std::fstream &matfile,std::map<std::string,double> & parameters);
virtual ~ElectronFluxConvection() {};
virtual void electron_flux(const FIELD_MATS &fields,
const GRAD_FIELD_MATS &gradFields,
DENS_MAT_VEC &flux)
{
// flux = n v
electron_convection(fields,flux);
};
};
}
#endif
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