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1;
clear all;
t0 = clock (); % we will use this latter to calculate elapsed time
% load useful functions;
useful_functions;
% some physical constants
useful_constants;
% load atom energy levels and decay description
four_levels;
%three_levels;
%two_levels;
% load EM field description
field_description;
Nfreq=length(modulation_freq);
%tune probe frequency
detuning_p=0;
N_detun_steps=100;
detuning_p_min=-1;
detuning_p_max=-detuning_p_min;
detuning_freq=zeros(1,N_detun_steps+1);
kappa_p =zeros(1,N_detun_steps+1);
kappa_m =zeros(1,N_detun_steps+1);
detun_step=(detuning_p_max-detuning_p_min)/N_detun_steps;
% now we create Liouville indexes list
[N, rhoLiouville_w, rhoLiouville_r, rhoLiouville_c]=unfold_density_matrix(Nlevels,Nfreq);
rhoLiouville=zeros(N,1);
% calculate E_field independent properties of athe atom
% to be used as sub matrix templates for Liouville operator matrix
[L0m, polarizability_m]=L0_and_polarization_submatrices( ...
Nlevels, ...
H0, g_decay, g_dephasing, dipole_elements ...
);
for detuning_p_cntr=1:N_detun_steps+1;
wp0=w12;
detuning_p=detuning_p_min+detun_step*(detuning_p_cntr-1);
wp=wp0+detuning_p;
wm=wd-(wp-wd);
%modulation_freq=[0, wp, wd, wm, -wp, -wd, -wm, wp-wd, wd-wp];
%E_field =[0, Ep, Ed, Em, Epc, Edc, Emc, 0, 0 ];
modulation_freq=[0, wp, wd, -wp, -wd, wp-wd, wd-wp];
E_field =[0, Ep, Ed, Epc, Edc, 0, 0 ];
Nfreq=length(modulation_freq);
% now we create Liouville indexes list
[N, rhoLiouville_w, rhoLiouville_r, rhoLiouville_c]=unfold_density_matrix(Nlevels,Nfreq);
% Liouville operator matrix construction
L=Liouville_operator_matrix(
N,
L0m, polarizability_m,
E_field,
modulation_freq, rhoLiouville_w, rhoLiouville_r, rhoLiouville_c
);
%use the fact that sum(rho_ii)=1 to constrain solution
[rhoLiouville_dot, L]=constrain_rho_and_match_L(
N, L,
modulation_freq, rhoLiouville_w, rhoLiouville_r, rhoLiouville_c);
%solving for density matrix vector
rhoLiouville=L\rhoLiouville_dot;
%rho_0=rhoOfFreq(rhoLiouville, 1, Nlevels, Nfreq); % 0 frequency,
%rho_p=rhoOfFreq(rhoLiouville, 2, Nlevels, Nfreq); % probe frequency
%rho_d=rhoOfFreq(rhoLiouville, 3, Nlevels, Nfreq); % drive frequency
%rho_m=rhoOfFreq(rhoLiouville, 4, Nlevels, Nfreq); % opposite sideband frequency
kappa_p(detuning_p_cntr)=susceptibility(freq2index(wp,modulation_freq), rhoLiouville, dipole_elements, Nlevels, Nfreq);
%kappa_m(detuning_p_cntr)=susceptibility(4, rhoLiouville, dipole_elements, Nlevels, Nfreq);
detuning_freq(detuning_p_cntr)=detuning_p;
%kappa_p_re=real(kappa_p);
%kappa_p_im=imag(kappa_p);
endfor
figure(1); plot(detuning_freq, real(kappa_p)); title("probe dispersion");
figure(2); plot(detuning_freq, imag(kappa_p)); title("probe absorption");
%figure(3); plot(detuning_freq, real(kappa_m)); title("off resonant sideband dispersion");
%figure(4); plot(detuning_freq, imag(kappa_m)); title("off resonant absorption");
elapsed_time = etime (clock (), t0)
% vim: ts=2:sw=2:fdm=indent
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