Metamaterial relative permittivity

Hi everybody. I realized with MATLAB (not LiveLink) a metamaterial permittivity distribution. It consist in (x,y) point coordinates and relative "epsilon" values, like:

x y val
0 1 0
....
4 2 10
....


since my structure should be a lens, so a flat object:

1. should I word in 2D or still 3D COMSOL environment?
2. How can I use/remap/don't know the epsilon informations I got with COMSOL to reproduce the lens in the program?

Thanks!