negative permittivity

[sitangshu]

Dear all,

Hope you are all at high spirits!
One doubt is bothering me.... can BSE able to justify negative permittivity in metamaterials?

Regards,
Sitangshu

[claudio]

Dear Sitangshu

I think you can get a negative permittivity with BSE or in independent particle approximation,

the problem is that metamaterials are usually large systems to simulate, but if you find a system that you can simulate with Yambo, why not?

moreover, are excitonic effects important for metameterials? I don't know, maybe at the beginning it is better you start with independent particle approximation

best
Claudio