Hi all I want to design a Few mode fiber with graded index core. when it is step index there is no problem. But I am getting difficulties for graded index core design. I hv used analytical functions to define the graded index core. But when it is linked into the material it is showing unknown variables. Then I hv defined the core index under global definition then the design is working but all the expected LP modes are not coming.
In this regard I need the help. Thank you in advance