arxiv.org/pdf/quant-ph/0106078v1.pdf
[L:arxiv.org/pdf/quant-ph/0106078v1.pdf]arxiv.org/pdf/quant-ph/0106078v1.pdf[/L]arxiv.org/pdf/quant-ph/0106078v1.pdf
wigner.elte.hu/koltai/labor/parts/22qe.pdf
[L:wigner.elte.hu/koltai/labor/parts/22qe.pdf]wigner.elte.hu/koltai/labor/parts/22qe.pdf[/L]

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <X11/Xlib.h>


Display *dpy;
Window win;
GC gc;
double radian=(180.0/M_PI);


void pixel(int x,int y,int color)
{
XSetForeground(dpy,gc,color);
XDrawPoint(dpy, win, gc, x,y);
}
void line(int x1,int y1,int x2,int y2,int color)
{
XSetForeground(dpy,gc,color);
XDrawLine(dpy, win, gc, x1,y1,x2,y2);
}
double sqr(double n) // x^2
{
return n*n;
}
double doublerand() //random szam 0.0-tol 1.0-ig
{
return (double)(rand()%10000)/10000.0;
}



struct vec2d
{
double x,y;

vec2d() {x=0;y=0;}
};
void add_amp(vec2d *v,double phase,double ax,double ay)
{
v->x += sin(phase)*ax;
v->y += cos(phase)*ay;
};
void add_polarizer(vec2d *v,double phase)
{
v->x *= sin(phase);
v->y *= cos(phase);
};
double dot(vec2d *v1,vec2d *v2)
{
return v1->x*v2->x + v1->y*v2->y;
}
void add_quarterwaveplate(vec2d *v,double phase,double dist,double qwp,double ax,double ay,double dphase)
{
vec2d axis_fast,axis_slow,input_wave;

add_amp(&axis_fast,qwp,1.0,1.0);
add_amp(&axis_slow,qwp+90.0/radian,1.0,1.0);
add_amp(&input_wave,phase,1.0,1.0);

double amp_fast=dot(&axis_fast,&input_wave);
double amp_slow=dot(&axis_slow,&input_wave);

amp_fast=cos(dist+dphase)*amp_fast;
amp_slow=sin(dist+dphase)*amp_slow;//-+90 phase shift

v->x += (axis_fast.x*amp_fast + axis_slow.x*amp_slow)*ax;
v->y += (axis_fast.y*amp_fast + axis_slow.y*amp_slow)*ay;
};
double probalbility(vec2d *v)
{
return (sqr(v->x) + sqr(v->y));
}


int main()
{
dpy = XOpenDisplay(0);
win = XCreateSimpleWindow(dpy, DefaultRootWindow(dpy), 0,0, 800, 550, 0,0,0);

XSelectInput(dpy, win, StructureNotifyMask);
XMapWindow(dpy, win);
gc = XCreateGC(dpy, win, 0, 0);

for(;;) { XEvent e; XNextEvent(dpy, &e); if (e.type == MapNotify) break; }



for(int x=0;x<400;x++)
{
pixel(x,500,0x008800);
pixel(x,300,0x008800);
pixel(x,100,0x008800);
}



for(int ds_x=0;ds_x<400;ds_x++)//Ds position -+4mm
{
int photon_counter=0;
int maxphoton=400;
int maxwide=10;

int qwplate_on=1;
int eraser_on=1;
double eraser_alpha=22.5/radian;
// double eraser_alpha=(-22.5)/radian;

// if(eraser_on) maxphoton*=4;//lathatosag



for(int p=0;p<maxphoton;p++)// max number of photon
{
double dphase=M_PI*2*doublerand();
#if 1
double photon_pol_a=M_PI*2*doublerand();
double photon_pol_b=photon_pol_a+M_PI/2;
#else
double photon_pol_a=0; //polarized lightsource
if(doublerand()>0.5) photon_pol_a=M_PI/2;
double photon_pol_b=photon_pol_a+M_PI/2;
if(doublerand()>0.5) photon_pol_b=photon_pol_a-M_PI/2;
#endif


double ds_distance=1250.0-420.0;//mm 125-42 cm
double dp_distance=980.0; //98 cm
double wavelength=702.2e-6;//mm e-9m
double k=2.0*M_PI/wavelength;
vec2d amp_dp,amp_ds;

if(eraser_on)
{
if(doublerand()>0.5)
{
photon_pol_a=eraser_alpha;//backwark causality
photon_pol_b=eraser_alpha+90.0/radian;
}
else
{
photon_pol_a=eraser_alpha+90.0/radian;
photon_pol_b=eraser_alpha;
}
}


double hole_dist=0.2;//0.2
double hole_wide=0.2;//200 micrometer wide
double ds_pos=4.0*(double)(ds_x-200)/200.0;//+-4mm Ds position
int side=rand()%2;

for(int w=0;w<maxwide;w++)//slit wide
{
double hole1x=hole_dist/2.0 + hole_wide*(double)w/maxwide;//hole
double hole2x=-hole_dist/2.0 - hole_wide*(double)w/maxwide;
double dist1=sqrt(sqr(ds_pos - hole1x) + sqr(ds_distance));
double dist2=sqrt(sqr(ds_pos - hole2x) + sqr(ds_distance));


if(qwplate_on)
{
if(side==0)
{
add_amp(&amp_dp,photon_pol_a ,0.5,0.5);
add_amp(&amp_dp,photon_pol_a ,0.5,0.5);

add_quarterwaveplate(&amp_ds,photon_pol_b , dist1*k,-45.0/radian,0.5, 0.5,dphase);
add_quarterwaveplate(&amp_ds,photon_pol_b , dist2*k, 45.0/radian,0.5, 0.5,dphase);
}
else
{
add_amp(&amp_dp,photon_pol_b ,0.5,0.5);
add_amp(&amp_dp,photon_pol_b ,0.5,0.5);

add_quarterwaveplate(&amp_ds,photon_pol_a , dist1*k,-45.0/radian,0.5, 0.5,dphase);
add_quarterwaveplate(&amp_ds,photon_pol_a , dist2*k, 45.0/radian,0.5, 0.5,dphase);
}
}
else
{
add_amp(&amp_dp,photon_pol_a ,0.5,0.5);
add_amp(&amp_dp,photon_pol_a ,0.5,0.5);
add_amp(&amp_ds,photon_pol_b +dist1*k ,0.5,0.5);
add_amp(&amp_ds,photon_pol_b +dist2*k ,0.5,0.5);
}
}
if(eraser_on) add_polarizer(&amp_dp,eraser_alpha);// polarizer before Dp

amp_dp.x/=maxwide;//normalized
amp_dp.y/=maxwide;
amp_ds.x/=maxwide;
amp_ds.y/=maxwide;


if((probalbility(&amp_dp))>doublerand())
if((probalbility(&amp_ds))>doublerand())
photon_counter+=1;
}
pixel(ds_x,500-photon_counter,0xffff00);
}

/*
double dist1=0.0;
for(int p=0;p<1000;p++)//quarterwaveplate
{
vec2d amp_dp,amp_ds;
add_quarterwaveplate(&amp_ds,0.0/radian , dist1*M_PI/100.0,45.0/radian,0.5, 0.5);

line(200,200,200+200.0*amp_ds.x,200+200.0*amp_ds.y,0x00ff00);
dist1+=5.0;

XFlush(dpy);
getchar();
}
*/
XFlush(dpy);
getchar();

return 0;
}