Re: 3D certitudes (=doubts cleared up)

On Fri, 17 Nov 2006, Vincent Paeder wrote:
> I understand that, I just suppose that if I want to simulate a slab of 
> finite thickness, having pmls can be an advantage. In fact I haven't 
> been very clear but what I want to simulate ultimately is a slab of 
> finite thickness. I had obtained results that I didn't understand but 
> these misunderstandings are, I believe, all related to band folding. I 
> just hadn't figured it out before. And I was trying things which were a 
> bit of a nonsense I reckon. Sorry for that! Many thanks for your help,

PMLs (absorbing boundary layers) are unnecessary for the guided modes of a 
slab.  You only really want PML for modes that radiate, e.g. leaky modes 
above the light line or in a cavity.

Steven