Transfer matrix method for plasmonics

I run the shared the jreftran.m which has been designed for two layers:

delta=1i*g.*d.*ct;
M=zeros(2,2,length(d));
for j=1:length(d)
    M(1,1,j)=cos(delta(j));
    M(1,2,j)=1i./eta(j).*sin(delta(j));
    M(2,1,j)=1i*eta(j).*sin(delta(j));
    M(2,2,j)=cos(delta(j));
end    
M_t=[1,0;0,1]; %M total
for j=2:(length(d)-1)
    M_t=M_t*M(:,:,j);
end

But I intend to move to three or more layers using the same matrix method.

Answer 1

[Vidhi Agarwal]

Hi @SCIUSCIA

By multiplying the matrices corresponding to each layer, you can adapt the code to handle three or more levels by iterating over all layers using the matrix approach. Making sure that the matrix multiplication accurately adds up each layer's impact on the overall transfer matrix is crucial.

The modified code for three or more layers with matrix multiplication will be:

delta = 1i * g .* d .* ct;
num_layers = length(d);

% Initialize the layer matrices
M = zeros(2, 2, num_layers);

% Compute the matrix for each layer
for j = 1:num_layers
    M(1, 1, j) = cos(delta(j));
    M(1, 2, j) = 1i / eta(j) * sin(delta(j));
    M(2, 1, j) = 1i * eta(j) * sin(delta(j));
    M(2, 2, j) = cos(delta(j));
end

% Initialize the total matrix as the identity matrix
M_t = eye(2);

% Multiply the matrices for all layers
for j = 1:num_layers
    M_t = M_t * M(:, :, j);
end

% Now M_t is the total transfer matrix for the entire stack of layers

Hope that Helps!