Quantum phase transition between cluster and antiferromagnetic states

Understand

We study a Hamiltonian system describing a three spin-1/2 cluster-like interaction competing with an Ising-like exchange.

• We show that the ground state in the cluster phase possesses symmetry protected topological order.
• A continuous quantum phase transition occurs as result of the competition between the cluster and Ising terms.
• At the critical point the Hamiltonian is self-dual.