include_globals.m

用S-Matrix算法计算光栅衍射问题。

%   Parameters of Incident Wave
global lambda0; % arbtrary unit *scalar*
global theta;   % incident angle *scalar*
global Littrow_angle; % Littrow angle for the -1st order
global incident_angle; % save the incident angle vector *vector*
global k0;      % propagation number in vaccum *scalar*

%   Parameters of Grating
global P; % layers of grating *scalar*
global bottom_y; % [y0,y1,...,yP] *vector[1,(P+1)]*
global thick_e; % [e1,e2,...,e(P-1)] *vector[1,(P-1)]*
global period_d; % period length of grating *scalar*
global epsilon_e; % [eps0,eps1,...,eps(P+1)] *vector[1,(P+1)]*
global miu_u; % [1.0,1.0,...,1.0] *vector[1,(P+1)]*,

%   Parameters of Corrugation
global corrugation_h; % [h0,h1,..,hP] *vector[1,(P+1)]*
global period_k; % k number for describing corrugation of sine gratings *scalar*
global Lmn_plus; % page 0 to page P,[+L(-N,-N),+L(-N,-(N-1)),...,+L(-N,N);...;+L(N,-N),+L(N,-(N-1)),...,+L(N,N)], *matrix[(2N+1),(2N+1),(P+1)]*
global Lmn_minus; % page 0 to page P,[-L(-N,-N),-L(-N,-(N-1)),...,-L(-N,N);...;-L(N,-N),-L(N,-(N-1)),...,-L(N,N)], *matrix[(2N+1),(2N+1),(P+1)]*

%   Truncation Parameter
global N; % the subscript ranges from -N to N,i.e. (2N+1) in total *scalar*
global NN; % all N values need to be compuated
global DIM; %dimension of the matrix

%   Parameters of Diffraction Orders
global propagation_k; % [k0,k1,...,k(P+1)],propagation numbers in different layers *vector[1,(P+2)]*
global alpha_a; % [a(-N),a(-(N-1)),...,a(0),...,a(N-1),a(N)],x components of propagation numbers *vector[1,(2N+1)]*
global beta_b; % [b(0,-N),b(0,-(N-1)),...,b(0,N);...;b(P+1,-N),b(P+1,-(N-1)),...,b(P+1,N)], y components of k, *matrix[(P+2),(2N+1)]*
global H_transmission; % [-H(-N),-H(-(N-1)),...,-H(N)], transmitted components of magnetic field for TM wave, *vector[1,(2N+1)]*
global E_transmission; % [-E(-N),-E(-(N-1)),...,-E(N)], transmitted components of electric field for TE wave, *vector[1,(2N+1)]*
global H_reflection; % [+H(-N),+H(-(N-1)),...,+H(N)], reflected components of magnetic field for TM wave, *vector[1,(2N+1)]*
global E_reflection; % [+E(-N),+E(-(N-1)),...,+E(N)], reflected components of electric field for TE wave, *vector[1,(2N+1)]*
global TE_reflection; % record the computation results
global TE_transmission;
global TM_reflection;
global TM_transmission;
global TE_eta_reflection
global TE_eta_transmission
global TM_eta_reflection
global TM_eta_transmission

%   For analysis of convergence
global TM_reflection_eff_convergence
global TM_transmission_eff_convergence
global TE_reflection_eff_convergence
global TE_transmission_eff_convergence


%   For analysis of incident angles
global TM_reflection_eff_angle
global TM_transmission_eff_angle
global TE_reflection_eff_angle
global TE_transmission_eff_angle

%   For analysis of wavelengths
global TM_reflection_eff_lambda
global TM_transmission_eff_lambda
global TE_reflection_eff_lambda
global TE_transmission_eff_lambda

%   For analysis of corrugation
global TM_reflection_eff_corrugation
global TM_transmission_eff_corrugation
global TE_reflection_eff_corrugation
global TE_transmission_eff_corrugation