Variations of hodge structures of rank three k-Higgs bundles and moduli spaces of holomorphic triples

There is an isomorphism between the moduli spaces of sigma-stable holomorphic triples and some of the critical submanifolds of the moduli space of k-Higgs bundles of rank three, whose elements ( E, phi(k)) correspond to variations of Hodge structure, VHS. There are special embeddings on the moduli spaces of k-Higgs bundles of rank three. The main objective here is to study the cohomology of the critical submanifolds of such moduli spaces, extending those embeddings to moduli spaces of holomorphic triples.