I have a question about differing band structures for what (seems to me) to be the same structure.
To put it simply, consider scripting into mpb a single unit cell of a photonic crystal (I am using the Slanted Pore with 2 Slanted pores, but whichever one it is won't really matter) and obtaining the band structure. Now, consider scripting into MPB twelve unit cells of this photonic crystal stacked one on top another and obtaining the band structure. These band structures will not be the same! The band gap is actually much smaller for the unit cells stacked! Why is this? >From my understanding, MPB takes whatever structure it is given and stacks it >left to right, up and down and forwards and back to (in a sense) exhaust all >of free space. So whether we exhaust all of free space with one unit cell of >the photonic crystal or in chunks of eight unit cells, shouldn't we get the >same band structure? The control files and the images of the resulting band structures can be found at https://www.dropbox.com/sh/0a1z64u82prmp2z/6H2J_pg2OQ. (The first Brioullin Zone has points taken from http://en.wikipedia.org/wiki/File:TET.PNG ). If someone could help me understand why these two band structures are different, I'd greatly appreciate it! Thanks! Pranai
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