Thanks for your answer.nYes, according to your answer, I have put the substrate in the figure. Now I have specified the distance in the figures. Please determine that they are drawn correctly?.Besides, I have two questions. n1- If the wavelength range,(1530 nm - 1560 nm), is considered instead of a wavelength, should be the distance from the boundary condition to the waveguide at least half the wavelength greater? nFor example in wavelength range (1530 - 1560), distance <= 1560/2.nn2- Also, in the figure related to the cross-section in the coordinates (y-z), if the upper boundary condition is the metal type, what should be the distance boundary condition metal to the waveguide? Is it possible to consider the PML boundary condition for metal? nn