Hello All, Im trying to calculate the effective refractive index of a mode, and for this Im using the (display group velocities) function.
One of the velocity outputs of my simulation is velocity:, 2, #(-4.90451745978336e-6 -4.90681942731539e-6 0.912710199555404), #(-4.80093195197473e-5 -4.8009048331541e-5 0.91561875483683), #(1.31121732587251e-5 1.30097505968729e-5 0.118793068102301), #(3.30328251620264e-4 3.30323377140027e-4 -0.300956120203374), #(4.63721694288894e-4 4.63785289361192e-4 -0.304113410536935), #(3.42546127623946e-7 -3.23401587667056e-7 0.0272995328645365), #(1.21167087607205e-4 1.24729489218949e-4 0.026147706220866), #(9.11879799925218e-4 9.14055080695155e-4 0.238485996216362) My waveguide is 3D, with the propagation in the z direction. So I have selected only the propagation velocity in the z direction (vz) (The 3rd component of any set of velocities) and used this to calculate the effective index as (1 / vz). (Since vz is in units of c and the effective index is c/ velocity inside the medium). But this gives me values of 1.1, 1.5 etc, where as the expected refractive index values are around 3.6 (This is a GaAs waveguide). Im getting the same results when I try to calculate effective index as k-z / k0. I have a feeling that Im getting the units of 'k' and 'group velocity' wrong. Can you please let me know how to interpret my results and how to correctly calculate the effective index? Thank you very much.
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