GW demonstrates different definitions of gaussian line widths

1/e, 1/e^2, and FWHM.

by Chuck DiMarzio Northeastern University August 2009

SYNTAX; gw;

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x=[-2:0.02:2]; % x axis variable
g=exp(-x.^2);  % Gaussian beam of unit width
fig1=figure;plot(x,g,'-',...
                 [0,1],exp(-1)*[1,1],'-',...
                 [0,sqrt(log(2))],[1,1]/2,'-');
text(0.2,exp(-1)+.05,'t_{1/e}');
text(0.2,0.55,'t_{1/2}');
xlabel('\tau, time');
ylabel('\gamma(\tau)');

fig2=figure;plot(x,g,'-',...
                 [0,1],exp(-1)*[1,1],'-',...
                 [0,sqrt(log(2))],[1,1]/2,...,'-',...
                 sqrt(log(2))*[-1,-1,1,1],[0.5,0.48,0.48,0.5],'-');
text(-0.5,exp(-1)+.06,'$\omega_{FWHM}$','Interpreter','LaTeX');% center
text(0.2,0.58,'$\omega_{1/2}$','Interpreter','LaTeX');% top
text(0.2,0.30,'$\omega_{1/e}$','Interpreter','LaTeX');%bottom
xlabel('\omega');
ylabel('$\tilde{\gamma}(\omega)$','Interpreter','LaTeX');