Bulk-edge correspondence in the Haldane phase of the bilinear-biquadratic spin-1 Hamiltonian

The Haldane phase is the prototype of symmetry protected topological (SPT) phases spin chain systems. It can be by several symmetries having in common degeneracy entanglement spectrum. Here we explore depth this for spin-1 AKLT and bilinear-biquadratic Hamiltonians show emergence a bulk-edge correspondence that relates low energy properties Hamiltonian periodic physical an open chain. We find spectrum described terms two spins-1/2 behaving as effective spins at end In case non-contiguous partitions, given spin-1/2 Heisenberg Hamiltonian, which suggests relationship between SPT conformal field theory. finally investigate string order parameter relation with correspondence.