ABSTRACT
Gerardo Ortiz Department of Physics, Indiana University, Bloomington, Indiana 47405, U.S.A.
Quantum matter often displays complex phase diagrams as a result of competing interactions, with orderings (states of matter) which are believed to be influenced by being in proximity to quantum critical points, e.g., high-Tc materials, heavy fermion compounds, and frustrated magnets. Each quantum phase is characterized by different behaviors of appropriate correlation functions, such as long-range order, or algebraic or exponential decay. Since entanglement is a property inherent in quantum states and is strongly related to quantum correlations, one would expect that the entanglement present in the ground state (GS) of the system changes substantially at a quantum phase transition (QPT), i.e., when there is a qualitative change in the behavior of the correlations between constituents. Obviously, the identification and quantification of those changes become issues of utmost relevance.
