Entanglement in a model with power law interactions

In this talk we present an exact approach to calculating the entanglement entropy in spin chains that are described by conformal theory at quantum criticality. The method was initially used to study entanglement in free fermions and the XY model, but it turns out that Kitaev chains with long-ranged power law interactions also fall in the same solvable class. We evaluate the Schmidt gap in the entanglement spectrum and use it to map out the phase diagram of the model.