Quantum correlations in anisotropic XY-spin chains in a transverse magnetic field

The well-known anisotropic XY spin chains in a transverse magnetic field are studied in the context of bipartite entanglement and quantum discord. By using Jordan-Wigner transformation, the model mapped onto a noninteracting spinless fermion model then, by accessing the energy spectrum we have found analytical formulas for concurrence and quantum discord based on reduced density matrix. We used the approach to go beyond the trivial nearest neighbours information, namely the second and third nearest neighbours. It is shown that far distance derivatives of quantum discord are able to capture XY-critical line and furthermore a signature of factorization points is observed.