Hình 3.5:
% do thi Pulse Energy vs. T_0 ung voi cac gia tri R khac nhau
clc; clear all; close all; syms E z nfi n_s0 l_s
hv=1.86e-19; % J - nang luong photon 1064 nm
gamma=0.6;
L=0.05; % mat mat do tan xa
l_m=5; % cm - chieu dai thanh hoat chat
r=0.18; % cm - ban kinh chum Gauss
A=pi*(r^2); % cm^2 - tiet dien chum tia
l_cav=12; % cm - chieu dai BCH
t_r=2*l_cav/3e10; % s - thoi gian anh sang di lai 1 luot trong BCH
sigma=2.7e-19; % cm^2 - tiet dien hap thu hieu dung cua hoat chat
sigma_gs=43e-19; % cm^2 - tiet dien hap thu cua Cr4+YAG o trang thai co ban
sigma_es=8.2e-19; % cm^2 - tiet dien hap thu cua Cr4+YAG o trang thai kich thich delta=sigma_es/sigma_gs; alpha=sigma_gs/(gamma*sigma); R=[0.5 0.6 0.7];mau='rbmgyk'; T0=linspace(0.001,1); for i=1:length(R) ni=(log(1/R(i))+log(1./T0.^2)+L)/(2*sigma*l_m); z=delta+(1-delta)*L./(2*sigma*l_m.*ni); e_max=1-z+z.*log(z); E=e_max.*(ni*l_m*hv*A)./(gamma*(1-delta)); figure(1);
plot(T0,E,mau(i)); ylim([0 0.1]); hold on; % grid on;
xlabel('T_0'); ylabel('E_m_a_x (J)'); legend('R = 0.5','R = 0.6','R = 0.7',1);
w1=-log(z)./(1-(z-1)./log(z)+(z-1).*log((z-1)/log(z))./log(z)); W=w1*t_r./(2*sigma*ni*l_m);
figure(2);
plot(T0,W*1e9,mau(i)); hold on; % grid on;
xlabel('T_0'); ylabel('W_p (ns)');
legend('R = 0.5','R = 0.6','R = 0.7',2);
end
Hình 3.6:
% do thi Pulse Energy vs. R ung voi cac gia tri T_0 khac nhau
clc; clear all; close all; syms E z nfi n_s0 l_s
hv=1.86e-19; % J - nang luong photon 1064 nm
gamma=0.6;
L=0.05; % mat mat do tan xa
l_m=5; % cm - chieu dai thanh hoat chat
r=0.18; % cm - ban kinh chum Gauss
A=pi*(r^2); % cm^2 - tiet dien chum tia
l_cav=12; % cm - chieu dai BCH
t_r=2*l_cav/3e10; % s - thoi gian anh sang di lai 1 luot trong BCH
sigma=2.7e-19; % cm^2 - tiet dien hap thu hieu dung cua hoat chat
sigma_gs=4.3e-18; % cm^2 - tiet dien hap thu cua Cr4+YAG o trang thai co ban
sigma_es=8.2e-19; % cm^2 - tiet dien hap thu cua Cr4+YAG o trang thai kich thich delta=sigma_es/sigma_gs; alpha=sigma_gs/(gamma*sigma); T0=[0.65 0.7 0.75];mau='rbmgyk'; R=linspace(0.001,1); for i=1:length(T0) ni=(log(1./R)+log(1/T0(i)^2)+L)/(2*sigma*l_m); z=delta+(1-delta)*L./(2*sigma*l_m.*ni); e_max=1-z+z.*log(z); E=e_max.*(ni*l_m*hv*A)./(gamma*(1-delta)); figure(1);
plot(R,E,mau(i)); ylim([0 0.1]); hold on; % grid on;
xlabel('R'); ylabel('E_m_a_x (J)');
legend('T_0 = 0.65','T_0 = 0.7','T_0 = 0.75',1);
w1=-log(z)./(1-(z-1)./log(z)+(z-1).*log((z-1)/log(z))./log(z)); W=w1*t_r./(2*sigma*ni*l_m);
figure(2);
plot(R,W*1e9,mau(i)); hold on; % grid on;
xlabel('R'); ylabel('W_p (ns)');
legend('T_0 = 0.65','T_0 = 0.7','T_0 = 0.75',2);
end
Hình 3.7:
% Tim R vs. T0 ung voi gia tri nang luong E cho truoc
clc; clear all; close all; syms R T0 ns0 ls
hv=1.86e-19; % J - nang luong photon 1064 nm
gamma=0.6;
L=0.05; % mat mat do tan xa
l_m=5; % cm - chieu dai thanh hoat chat
r=0.19; % cm - ban kinh chum Gauss
A=pi*(r^2); % cm^2 - tiet dien chum tia
l_cav=12; % cm - chieu dai BCH
t_r=2*l_cav/3e10; % s - thoi gian anh sang di lai 1 luot trong BCH
sigma=2.7e-19; % cm^2 - tiet dien hap thu hieu dung cua hoat chat
sigma_gs=43e-19; % cm^2 - tiet dien hap thu cua Cr4+YAG o trang thai co ban
sigma_es=8.2e-19; % cm^2 - tiet dien hap thu cua Cr4+YAG o trang thai kich thich
delta=sigma_es/sigma_gs; alpha=sigma_gs/(gamma*sigma); mau='rbmgyk';
E=[0.03 0.035 0.04]; % J - nang luong xung laser
for i=1:length(E)
ni=(log(1/R)+log(1./T0.^2)+L)/(2*sigma*l_m); z=delta+(1-delta)*L/(2*sigma*l_m*ni);
eq=(1-delta)*gamma*E(i)/(hv*A*ni*l_m)-1+z-z*log(z); figure(1);
set(h1,'Color',mau(i));xlim([0.3 1]); ylim([0.5 1]);
end
legend('E = 30 mJ','E = 35 mJ','E = 40 mJ');
Hình 3.8:
% do thi Pulse Width vs. T_0 ung voi cac gia tri R khac nhau
clc; clear all; close all; syms E z nfi n_s0 l_s
hv=1.86e-19; % J - nang luong photon 1064 nm
gamma=0.6;
L=0.05; % mat mat do tan xa
l_m=5; % cm - chieu dai thanh hoat chat
r=0.18; % cm - ban kinh chum Gauss
A=pi*(r^2); % cm^2 - tiet dien chum tia
l_cav=12; % cm - chieu dai BCH
t_r=2*l_cav/3e10; % s - thoi gian anh sang di lai 1 luot trong BCH
sigma=2.7e-19; % cm^2 - tiet dien hap thu hieu dung cua hoat chat
sigma_gs=43e-19; % cm^2 - tiet dien hap thu cua Cr4+YAG o trang thai co ban
sigma_es=8.2e-19; % cm^2 - tiet dien hap thu cua Cr4+YAG o trang thai kich thich delta=sigma_es/sigma_gs; alpha=sigma_gs/(gamma*sigma); R=[0.5 0.6 0.7];mau='rbmgyk'; T0=linspace(0.001,1); for i=1:length(R) ni=(log(1/R(i))+log(1./T0.^2)+L)/(2*sigma*l_m); z=delta+(1-delta)*L./(2*sigma*l_m.*ni); e_max=1-z+z.*log(z); E=e_max.*(ni*l_m*hv*A)./(gamma*(1-delta)); figure(1);
plot(T0,E,mau(i)); ylim([0 0.1]); hold on; % grid on;
xlabel('T_0'); ylabel('E_m_a_x (J)'); legend('R = 0.5','R = 0.6','R = 0.7',1);
w1=-log(z)./(1-(z-1)./log(z)+(z-1).*log((z-1)/log(z))./log(z)); W=w1*t_r./(2*sigma*ni*l_m);
figure(2);
plot(T0,W*1e9,mau(i)); hold on; % grid on;
xlabel('T_0'); ylabel('W_p (ns)');
legend('R = 0.5','R = 0.6','R = 0.7',2);