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#include "Material.h"
#include "ElectronPhononExchange.h"
#include "ATC_Error.h"
#include "LammpsInterface.h"
#include <iostream>
#include <vector>
#include <cmath>
using ATC_Utility::command_line;
using ATC_Utility::str2dbl;
using ATC_Utility::str2int;
using std::fstream;
using std::map;
using std::string;
using std::vector;
namespace ATC {
ElectronPhononExchangeLinear::ElectronPhononExchangeLinear(
fstream &fileId, map<string,double> & parameters)
: ElectronPhononExchange(),
exchangeCoef_(0)
{
if (!fileId.is_open()) throw ATC_Error("cannot open material file");
vector<string> line;
while(fileId.good()) {
command_line(fileId, line);
if (line.size() == 0) continue;
if (line[0] == "end") return;
else if (line[0] == "coefficient") {
exchangeCoef_ = str2dbl(line[1]);
parameters["electron_phonon_exchange_coefficient"] = exchangeCoef_;
}
else {
throw ATC_Error( "unrecognized material function "+line[0]);
}
}
}
ElectronPhononExchangePowerLaw::ElectronPhononExchangePowerLaw(
fstream &fileId, map<string,double> & parameters)
: ElectronPhononExchange(),
exchangeCoef_(0),
exponent_(1)
{
if (!fileId.is_open()) throw ATC_Error("cannot open material file");
vector<string> line;
while(fileId.good()) {
command_line(fileId, line);
if (line.size() == 0) continue;
if (line[0] == "end") return;
else if (line[0] == "coefficient") {
exchangeCoef_ = str2dbl(line[1]);
parameters["electron_phonon_exchange_coefficient"] = exchangeCoef_;
}
else if (line[0] == "exponent") {
exponent_ = str2int(line[1]);
}
else {
throw ATC_Error( "unrecognized material function "+line[0]);
}
}
}
ElectronPhononExchangeHertel::ElectronPhononExchangeHertel(fstream &fileId,
map<string,double> & parameters,
Material * material)
: ElectronPhononExchange(),
exchangeCoef_(0),
debeyeTemperature_(1),
massEnhancement_(0),
material_(material)
{
if (!fileId.is_open()) throw ATC_Error("cannot open material file");
vector<string> line;
while(fileId.good()) {
command_line(fileId, line);
if (line.size() == 0) continue;
if (line[0] == "end") break;
else if (line[0] == "debeye_temperature") {
debeyeTemperature_ = str2dbl(line[1]);
parameters["debeye_temperature"] = debeyeTemperature_;
}
else if (line[0] == "mass_enhancement") {
massEnhancement_ = str2dbl(line[1]);
parameters["mass_enhancement"] = massEnhancement_;
}
else {
throw ATC_Error( "unrecognized material function "+line[0]);
}
}
// coupling coefficient, eqn. 15 of Hertel 2002
double kb = LammpsInterface::instance()->kBoltzmann();
double hbar = LammpsInterface::instance()->hbar();
double PI = 3.141592653589793238;
exchangeCoef_ = 144.*1.0369*kb/(PI*hbar);
exchangeCoef_ *= massEnhancement_/pow(debeyeTemperature_,2);
}
bool ElectronPhononExchangeHertel::electron_phonon_exchange(const FIELD_MATS &fields,
DENS_MAT &flux)
{
FIELD_MATS::const_iterator tField = fields.find(TEMPERATURE);
FIELD_MATS::const_iterator etField = fields.find(ELECTRON_TEMPERATURE);
const DENS_MAT & T = tField->second;
const DENS_MAT & Te = etField->second;
// flux = g C_e (T_e - T_p)^5 / T_e
flux = (Te - T).pow(5);
flux /= Te;
flux *= exchangeCoef_;
material_->electron_heat_capacity(fields,capacityWorkspace_);
flux*= capacityWorkspace_;
return true;
}
}
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