Can we achieve coherence/high directivity by polarisation?

I can understand little bit what coherence means and little bit what is polarisation means. The question is there a way to achieve coherence by polarisation? Specifically consider a source of dipole. Can we add some material or metamaterial of required sizes in front of the dipole so that we achieve coherence wave once it comes out of the material or metamaterial?

EDIT: If not coherence can we achieve higher direcivity? In other words can we accumulate all the energy in a particular angle or angle 0 with the help of metamaterial?