I tried to reproduce results from this paper. I got stuck at equation (28), where the grating is defined. The problem I had with (28) is the parameter “m”, the induced-index fringe modulation. The paper says it is 0 <= m <= 1.0, but I could not find the value for this parameter that is actually used in the paper. Its value will certainly influence the results. You cannot reproduce Fig. 10 b without it. But I could not find its value specified anywhere.