Construction of local order parameters from non-vanishing mutual information

In the recent decades, raising attention has been paid in the study of quantum phase transitions (QPTs) from quantum information perspectives. In this talk, we will present a scheme in constructing the local order parameters by investigating the spectra of the reduced density matrices that are used to calculate the mutual information. We will briefly review the relation between non-vanishing mutual information and the presence of long-range correlation in a system. In particular, we will illustrate our scheme using the numerical exact diagonalization result of the one-dimensional Hubbard model.