// Organic Photovoltaic Device Model - a drift diffusion base/Shockley-Read-Hall

// model for organic solar cells.

// Copyright (C) 2012 Roderick C. I. MacKenzie

//

// roderick.mackenzie@nottingham.ac.uk

// www.roderickmackenzie.eu

// Room B86 Coates, University Park, Nottingham, NG7 2RD, UK

//

// This program is free software; you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation; either version 2 of the License, or

// (at your option) any later version.

//

// This program is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

// GNU General Public License for more details.

//

// You should have received a copy of the GNU General Public License along

// with this program; if not, write to the Free Software Foundation, Inc.,

// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <math.h>

#include "sim.h"

#include "solver.h"

#include "buffer.h"

#include "log.h"

double min_pos_error = 1e-4;

void pos_dump(struct device *in)

{

if (get_dump_status(dump_first_guess) == TRUE) {

char out_dir[1000];

join_path(2, out_dir, in->outputpath, "equilibrium");

struct buffer buf;

buffer_init(&buf);

char name[200];

int band = 0;

int i = 0;

FILE *out;

out = fopena(in->outputpath, "first_guess.dat", "w");

for (i = 0; i < in->ymeshpoints; i++) {

fprintf(out, "%e %e %e\n", in->ymesh[i], in->Fn[i],

in->Fp[i]);

}

fclose(out);

out = fopena(in->outputpath, "first_guess_Fi.dat", "w");

for (i = 0; i < in->ymeshpoints; i++) {

fprintf(out, "%e %e\n", in->ymesh[i], in->Fi[i]);

}

fclose(out);

buffer_malloc(&buf);

sprintf(name, "%s%s", "first_guess_Ec", ".dat");

buf.y_mul = 1.0;

buf.x_mul = 1e9;

strcpy(buf.title, "LUMO energy - position");

strcpy(buf.type, "xy");

strcpy(buf.x_label, "Position");

strcpy(buf.y_label, "LUMO");

strcpy(buf.x_units, "nm");

strcpy(buf.y_units, "$E_{LUMO}$");

buf.logscale_x = 0;

buf.logscale_y = 0;

buffer_add_info(&buf);

buffer_add_xy_data(&buf, in->ymesh, in->Ec, in->ymeshpoints);

buffer_dump_path(out_dir, name, &buf);

buffer_free(&buf);

buffer_malloc(&buf);

sprintf(name, "%s%s", "first_guess_Ev", ".dat");

buf.y_mul = 1.0;

buf.x_mul = 1e9;

strcpy(buf.title, "HOMO energy - position");

strcpy(buf.type, "xy");

strcpy(buf.x_label, "Position");

strcpy(buf.y_label, "LUMO");

strcpy(buf.x_units, "nm");

strcpy(buf.y_units, "$E_{HOMO}$");

buf.logscale_x = 0;

buf.logscale_y = 0;

buffer_add_info(&buf);

buffer_add_xy_data(&buf, in->ymesh, in->Ev, in->ymeshpoints);

buffer_dump_path(out_dir, name, &buf);

buffer_free(&buf);

out = fopena(in->outputpath, "first_guess_n.dat", "w");

for (i = 0; i < in->ymeshpoints; i++) {

fprintf(out, "%e %e\n", in->ymesh[i], in->n[i]);

}

fclose(out);

out = fopena(in->outputpath, "first_guess_p.dat", "w");

for (i = 0; i < in->ymeshpoints; i++) {

fprintf(out, "%e %e\n", in->ymesh[i], in->p[i]);

}

fclose(out);

out = fopena(in->outputpath, "first_guess_phi.dat", "w");

for (i = 0; i < in->ymeshpoints; i++) {

fprintf(out, "%e %e\n", in->ymesh[i], in->phi[i]);

}

fclose(out);

out = fopena(in->outputpath, "first_guess_np.dat", "w");

for (i = 0; i < in->ymeshpoints; i++) {

fprintf(out, "%e %e %e\n", in->ymesh[i], in->n[i],

in->p[i]);

}

fclose(out);

out = fopena(in->outputpath, "first_guess_np_trap.dat", "w");

for (i = 0; i < in->ymeshpoints; i++) {

fprintf(out, "%e ", in->ymesh[i]);

for (band = 0; band < in->srh_bands; band++) {

fprintf(out, "%e %e ", in->nt[i][band],

in->pt[i][band]);

}

fprintf(out, "\n");

}

fclose(out);

}

}

double get_p_error(struct device *in, double *b)

{

double tot = 0.0;

int i;

for (i = 0; i < in->ymeshpoints; i++) {

if ((in->interfaceleft == TRUE) && (i == 0)) {

} else

if ((in->interfaceright == TRUE)

&& (i == in->ymeshpoints - 1)) {

} else {

tot += fabs(b[i]);

}

}

return tot;

}

int solve_pos(struct device *in)

{

if (get_dump_status(dump_iodump) == TRUE)

printf_log("Solve pos\n");

int i;

int N = in->ymeshpoints * 3 - 2;

int M = in->ymeshpoints;

int *Ti = malloc(N * sizeof(int));

int *Tj = malloc(N * sizeof(int));

double *Tx = malloc(N * sizeof(double));

double *b = malloc(M * sizeof(double));

double phil;

double phic;

double phir;

double yl;

double yc;

double yr;

double dyl;

double dyr;

double dyc = 0.0;

int ittr = 0;

int pos = 0;

double error = 1000;

double el = 0.0;

double ec = 0.0;

double er = 0.0;

double e0 = 0.0;

double e1 = 0.0;

int pos_max_ittr = 250;

int quit = FALSE;

int adv_step = 0;

int adv = FALSE;

int band;

double kTq = (in->Te[0] * kb / Q);

do {

if (in->interfaceleft == TRUE) {

in->phi[0] = in->Vl;

}

if (in->interfaceright == TRUE) {

in->phi[in->ymeshpoints - 1] = in->Vr;

}

pos = 0;

for (i = 0; i < in->ymeshpoints; i++) {

if (i == 0) {

phil = in->Vl;

el = in->epsilonr[0] * epsilon0;

yl = in->ymesh[0] - (in->ymesh[1] -

in->ymesh[0]);

} else {

el = in->epsilonr[i - 1] * epsilon0;

phil = in->phi[i - 1];

yl = in->ymesh[i - 1];

}

if (i == (in->ymeshpoints - 1)) {

phir = in->Vr;

er = in->epsilonr[i] * epsilon0;

yr = in->ymesh[i] + (in->ymesh[i] -

in->ymesh[i - 1]);

} else {

er = in->epsilonr[i + 1] * epsilon0;

phir = in->phi[i + 1];

yr = in->ymesh[i + 1];

}

yc = in->ymesh[i];

dyl = yc - yl;

dyr = yr - yc;

dyc = (dyl + dyr) / 2.0;

ec = in->epsilonr[i] * epsilon0;

e0 = (el + ec) / 2.0;

e1 = (ec + er) / 2.0;

phic = in->phi[i];

double dphidn = 0.0;

if (adv == FALSE) {

dphidn =

(Q / (kb * in->Tl[i])) * in->Nc[i] *

exp(((in->Fi[i] -

(-in->phi[i] - in->Xi[i]))) / (kTq));

} else {

dphidn =

get_dn_den(in->Fi[i] - in->Ec[i], in->Tl[i],

in->imat[i]);

}

double dphidp = 0.0;

if (adv == FALSE) {

dphidp =

-(Q / (kb * in->Tl[i])) * in->Nv[i] *

exp((((-in->phi[i] - in->Xi[i] -

in->Eg[i]) - in->Fi[i])) / (kTq));

} else {

dphidp =

-get_dp_den(in->xp[i] - in->tp[i],

in->Tl[i], in->imat[i]);

}

double dphil = e0 / dyl / dyc;

double dphic = -(e0 / dyl / dyc + e1 / dyr / dyc);

double dphir = e1 / dyr / dyc;

double dphil_d = dphil;

double dphic_d = dphic;

double dphir_d = dphir;

if (in->interfaceleft == TRUE) {

if (i == 1) {

dphil_d = 0.0;

phil = in->Vl;

}

if (i == 0) {

dphil_d = 0.0;

dphic_d = 1e-6;

dphir_d = 0.0;

}

}

if (in->interfaceright == TRUE) {

if (i == in->ymeshpoints - 2) {

dphir_d = 0.0;

phir = in->Vr;

}

if (i == in->ymeshpoints - 1) {

dphil_d = 0.0;

dphic_d = 1e-6;

dphir_d = 0.0;

}

}

double dphi =

dphil * phil + dphic * phic + dphir * phir;

dphic_d += -Q * (dphidn - dphidp); // just put in the _d to get it working again.

//if (adv==TRUE)

//{

// for (band=0;band<in->srh_bands;band++)

// {

// dphic_d+=(-q*(in->dnt[i][band]-in->dpt[i][band]));

// }

//}

if (i != 0) {

Ti[pos] = i;

Tj[pos] = i - 1;

Tx[pos] = dphil_d;

pos++;

}

Ti[pos] = i;

Tj[pos] = i;

Tx[pos] = dphic_d;

pos++;

if (i != (in->ymeshpoints - 1)) {

Ti[pos] = i;

Tj[pos] = i + 1;

Tx[pos] = dphir_d;

pos++;

}

if ((in->interfaceleft == TRUE) && (i == 0)) {

b[i] = -0.0;

} else

if ((in->interfaceright == TRUE)

&& (i == in->ymeshpoints - 1)) {

b[i] = -0.0;

} else {

b[i] = -(dphi - Q * (in->n[i] - in->p[i] - in->Nad[i])); //

if (adv == TRUE) {

for (band = 0; band < in->srh_bands;

band++) {

b[i] +=

-(-Q *

(in->nt[i][band] -

in->pt[i][band]));

}

}

}

//in->n[i]=in->Nc[i]*exp(((in->Fi[i]-in->Ec[i])*q)/(kb*in->Tl[i]));

}

error = get_p_error(in, b);

solver(M, N, Ti, Tj, Tx, b);

for (i = 0; i < in->ymeshpoints; i++) {

if ((in->interfaceleft == TRUE) && (i == 0)) {

} else

if ((in->interfaceright == TRUE)

&& (i == in->ymeshpoints - 1)) {

} else {

double update;

//printf("%d\n",get_clamp_state());

double clamp_temp = 300.0;

update =

b[i] / (1.0 +

fabs(b[i] / in->posclamp /

(clamp_temp * kb / Q)));

in->phi[i] += update;

//printf("%le %le\n",i,b[i]);

}

}

//getchar();

for (i = 0; i < in->ymeshpoints; i++) {

in->Ec[i] = -in->phi[i] - in->Xi[i];

in->Ev[i] = -in->phi[i] - in->Xi[i] - in->Eg[i];

if (adv == FALSE) {

in->n[i] =

in->Nc[i] *

exp(((in->Fi[i] -

in->Ec[i]) * Q) / (kb * in->Tl[i]));

in->dn[i] =

(Q / (kb * in->Tl[i])) * in->Nc[i] *

exp((Q * (in->Fi[i] - in->Ec[i])) /

(kb * in->Tl[i]));

} else {

in->n[i] =

get_n_den(in->Fi[i] - in->Ec[i], in->Tl[i],

in->imat[i]);

in->dn[i] =

get_dn_den(in->Fi[i] - in->Ec[i], in->Tl[i],

in->imat[i]);

}

in->Fn[i] = in->Fi[i];

in->Fp[i] = in->Fi[i];

in->x[i] = in->phi[i] + in->Fn[i];

in->xp[i] = -(in->phi[i] + in->Fp[i]);

if (adv == FALSE) {

in->p[i] =

in->Nv[i] *

exp(((in->xp[i] -

in->tp[i]) * Q) / (kb * in->Tl[i]));

in->dp[i] =

(Q / (kb * in->Tl[i])) * in->Nv[i] *

exp(((in->xp[i] -

in->tp[i]) * Q) / (kb * in->Tl[i]));

} else {

in->p[i] =

get_p_den(in->xp[i] - in->tp[i], in->Tl[i],

in->imat[i]);

in->dp[i] =

get_dp_den(in->xp[i] - in->tp[i], in->Tl[i],

in->imat[i]);

}

for (band = 0; band < in->srh_bands; band++) {

//printf("%lf %lf\n",in->xpt[i][band],in->Fpt[i][band]);

//getchar();

in->Fnt[i][band] =

-in->phi[i] - in->Xi[i] +

dos_srh_get_fermi_n(in->n[i], in->p[i],

band, in->imat[i],

in->Te[i]);

in->Fpt[i][band] =

-in->phi[i] - in->Xi[i] - in->Eg[i] -

dos_srh_get_fermi_p(in->n[i], in->p[i],

band, in->imat[i],

in->Th[i]);

in->xt[i][band] = in->phi[i] + in->Fnt[i][band];

in->nt[i][band] =

get_n_pop_srh(in->xt[i][band] + in->tt[i],

in->Te[i], band, in->imat[i]);

in->dnt[i][band] =

get_dn_pop_srh(in->xt[i][band] + in->tt[i],

in->Te[i], band,

in->imat[i]);

in->xpt[i][band] =

-(in->phi[i] + in->Fpt[i][band]);

in->pt[i][band] =

get_p_pop_srh(in->xpt[i][band] - in->tpt[i],

in->Th[i], band, in->imat[i]);

in->dpt[i][band] =

get_dp_pop_srh(in->xpt[i][band] -

in->tpt[i], in->Th[i], band,

in->imat[i]);

}

}

update_arrays(in);

in->xnl_left = in->x[0];

in->xpl_left = in->xp[0];

if (error < 1) {

adv = TRUE;

}

//#ifdef print_newtonerror

if (get_dump_status(dump_print_pos_error) == TRUE)

printf_log("%d Pos error = %e %d\n", ittr, error, adv);

//#endif

#ifdef dump_converge

/*in->converge=fopena(in->outputpath,"converge.dat","a");

fprintf(in->converge,"%e\n",error);

fclose(in->converge); */

#endif

//double N=2.0*pow(((2.0*pi*kb*in->Tl[0]*in->me[0]*m0)/(hp*hp)),1.5);

//double test=N*exp((-3.000000e-03*Q)/(kb*in->Tl[0]));

//printf("Check now %e %e\n",get_n_den(-3.000000e-03,in->Tl[0],in->me[0],in->dostype[0],dos_all),test);

//getchar();

//getchar();

ittr++;

if (adv == TRUE) {

adv_step++;

}

if (ittr > pos_max_ittr) {

quit = TRUE;

}

if ((error < min_pos_error) && (adv_step > 3)) {

quit = TRUE;

}

} while (quit == FALSE);

//getchar();

pos_dump(in);

update_arrays(in);

if (in->srh_sim == TRUE) {

time_init(in);

}

in->odes += in->ymeshpoints;

for (i = 0; i < in->ymeshpoints; i++) {

in->nf_save[i] = in->n[i];

in->pf_save[i] = in->p[i];

in->nt_save[i] = 0.0; //in->nt[i];

in->pt_save[i] = 0.0; //in->pt[i];

}

free(Ti);

free(Tj);

free(Tx);

free(b);

printf_log("Solved pos\n");

printf_log("Vl=%le Vr=%le phi_mid=%le\n", in->Vl, in->Vr,

in->phi[in->ymeshpoints / 2]);

return 0;

}