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Nathalie Carrier

Damian, thank you for the reply, it helped me a lot ! You are right for the structure and I finaly did not use the PBG structure at all. Can I ask for 3 more questions about structure design ?

I want to simulate surface plasmons in a thin Ag layer (~40 nm thick) deposited on glass. The layer is perforated with a 2D array of circular air holes (close packed lattice, with lattice parameter 0.562nm). Light is propagating through the glass, the perforated Ag layer and then the air medium.

– I chose the simulation domain to be glass (n=1.5).
– I adjusted the simulation domain dimensions in order that it matches with the unit cell of my structure and used periodic boundaries conditions.
– I created a linear waveguide of silver (40 nm thick).
– I created cylinders made of air, their centers are separated by the pitch (562 nm).
– I created a linear waveguide of air.

I put in attached the final design, could you take a look at it ? I have two issues about it.

First, I wonder what would be the difference between a 3D block of Ag and the linear waveguide profile used ?
Then, some cylinders are not entirely in the simulation domain in order to define the unit cell, is that a problem ?
Finaly, I wish to study the structure not only at normal incidence but with an angle, how is that possible ? By tilting the imput plane or the structure (then I will have issues with the periodic conditions to define the 2D array…)

It would really help me if you had some piece of advice,
Thank you a lot !