2D modeSolver

essentially we are trying to solve the eigenproblem: eps^(-1)curl mu^(-1) curl E = omega^2 E
the operator, \eps^(-1)curl \mu^(-1) curl, is constructed using FDFD + PML, more can be found in,

• https://empossible.net/academics/emp5337/ FDFD section
• http://www.mit.edu/~wsshin/pdf/shin_dissertation_updated.pdf