function result = miecoated_prscan(m1,m2,y,nsteps) % Computation and plot of Mie Efficiencies of coated % spheres for given complex refractive-index ratios % m1,2=m1',2'+im1",2" in kernel and coating, resp. % and size parameters x=k0*a, y=k0*b, vs. x/y=1-wr (see below) % with nsteps increments % a,b=inner,outer sphere radius, using complex Mie coefficients % an and bn, according to Bohren and Huffman (1983) BEWI:TDD122 % result: m1,m2,x,y,wr, efficiencies for extinction (qext), % scattering (qsca), absorption (qabs), backscattering (qb), % qratio=qb/qsca, asymmetry parameter (asy=), % volume fraction of coating w= 1-(a/b)^3 = 1-(x/y)^3 % C. Mätzler, July 2002. m1p=real(m1); m1pp=imag(m1); m2p=real(m2); m2pp=imag(m2); nx=(1:nsteps)'; pr=(nx-0.5)/nsteps; % note that pr=a/b=(1-w)^(1/3) x=y*pr; for j = 1:nsteps a(j,:)=miecoated(m1,m2,x(j),y,1); end; output_parameters='m1(real,imag), m2(real, imag), x, y, Qext, Qsca, Qabs, Qb, , Qb/Qsca' % plotting the results plot(pr,a(:,1:5)) legend('Qext','Qsca','Qabs','Qb','') title(sprintf('Mie Efficiencies of coated sphere, y=%g, m1=%g+%gi, m2=%g+%gi ',y,m1p,m1pp,m2p,m2pp)) xlabel('a/b') result=a;