Homogenization of metamaterials is a crucial issue as it allows to describe
their optical response in terms of effective wave parameters as e.g.
propagation constants. In this paper we consider the possible homogenization of
chiral metamaterials. We show that for meta-atoms of a certain size a critical
density exists above which increasing coupling between neighboring meta-atoms
prevails a reasonable homogenization. On the contrary, a dilution in excess
will induce features reminiscent to photonic crystals likewise prevailing a
homogenization. Based on Bloch mode dispersion we introduce an analytical
criterion for performing the homogenization and a tool to predict the
homogenization limit. We show that strong coupling between meta-atoms of chiral
metamaterials may prevent their homogenization at all.Comment: 8 pages, 7 figure
